diff --git a/test/hotspot/jtreg/serviceability/dcmd/thread/ThreadDumpToFileTest.java b/test/hotspot/jtreg/serviceability/dcmd/thread/ThreadDumpToFileTest.java
index 4cf70d7c781..b2386adb617 100644
--- a/test/hotspot/jtreg/serviceability/dcmd/thread/ThreadDumpToFileTest.java
+++ b/test/hotspot/jtreg/serviceability/dcmd/thread/ThreadDumpToFileTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,7 +26,7 @@
  * @bug 8284161 8287008
  * @summary Basic test for jcmd Thread.dump_to_file
  * @library /test/lib
- * @run testng/othervm ThreadDumpToFileTest
+ * @run junit/othervm ThreadDumpToFileTest
  */
 
 import java.io.IOException;
@@ -37,16 +37,16 @@ import jdk.test.lib.dcmd.PidJcmdExecutor;
 import jdk.test.lib.process.OutputAnalyzer;
 import jdk.test.lib.threaddump.ThreadDump;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class ThreadDumpToFileTest {
+class ThreadDumpToFileTest {
 
     /**
      * Test thread dump, should be in plain text format.
      */
     @Test
-    public void testThreadDump() throws IOException {
+    void testThreadDump() throws IOException {
         Path file = genThreadDumpPath(".txt");
         testPlainThreadDump(file);
     }
@@ -55,7 +55,7 @@ public class ThreadDumpToFileTest {
      * Test thread dump in plain text format.
      */
     @Test
-    public void testPlainThreadDump() throws IOException {
+    void testPlainThreadDump() throws IOException {
         Path file = genThreadDumpPath(".txt");
         testPlainThreadDump(file, "-format=plain");
     }
@@ -64,7 +64,7 @@ public class ThreadDumpToFileTest {
      * Test thread dump in JSON format.
      */
     @Test
-    public void testJsonThreadDump() throws IOException {
+    void testJsonThreadDump() throws IOException {
         Path file = genThreadDumpPath(".json");
         threadDump(file, "-format=json").shouldMatch("Created");
 
@@ -85,21 +85,21 @@ public class ThreadDumpToFileTest {
      * Test that an existing file is not overwritten.
      */
     @Test
-    public void testDoNotOverwriteFile() throws IOException {
+    void testDoNotOverwriteFile() throws IOException {
         Path file = genThreadDumpPath(".txt");
         Files.writeString(file, "xxx");
 
         threadDump(file, "").shouldMatch("exists");
 
         // file should not be overridden
-        assertEquals(Files.readString(file), "xxx");
+        assertEquals("xxx", Files.readString(file));
     }
 
     /**
      * Test overwriting an existing file.
      */
     @Test
-    public void testOverwriteFile() throws IOException {
+    void testOverwriteFile() throws IOException {
         Path file = genThreadDumpPath(".txt");
         Files.writeString(file, "xxx");
         testPlainThreadDump(file, "-overwrite");
diff --git a/test/jdk/com/sun/management/HotSpotDiagnosticMXBean/DumpThreads.java b/test/jdk/com/sun/management/HotSpotDiagnosticMXBean/DumpThreads.java
index fe4efcf9800..174300af174 100644
--- a/test/jdk/com/sun/management/HotSpotDiagnosticMXBean/DumpThreads.java
+++ b/test/jdk/com/sun/management/HotSpotDiagnosticMXBean/DumpThreads.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,10 +27,10 @@
  * @summary Basic test for com.sun.management.HotSpotDiagnosticMXBean.dumpThreads
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm DumpThreads
- * @run testng/othervm -Djdk.trackAllThreads DumpThreads
- * @run testng/othervm -Djdk.trackAllThreads=true DumpThreads
- * @run testng/othervm -Djdk.trackAllThreadds=false DumpThreads
+ * @run junit/othervm DumpThreads
+ * @run junit/othervm -Djdk.trackAllThreads DumpThreads
+ * @run junit/othervm -Djdk.trackAllThreads=true DumpThreads
+ * @run junit/othervm -Djdk.trackAllThreadds=false DumpThreads
  */
 
 import java.lang.management.ManagementFactory;
@@ -47,10 +47,10 @@ import com.sun.management.HotSpotDiagnosticMXBean;
 import com.sun.management.HotSpotDiagnosticMXBean.ThreadDumpFormat;
 import jdk.test.lib.threaddump.ThreadDump;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class DumpThreads {
+class DumpThreads {
     private static final boolean TRACK_ALL_THREADS;
     static {
         String s = System.getProperty("jdk.trackAllThreads");
@@ -61,7 +61,7 @@ public class DumpThreads {
      * Thread dump in plain text format.
      */
     @Test
-    public void testPlainText() throws Exception {
+    void testPlainText() throws Exception {
         var mbean = ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class);
         Path file = genOutputPath("txt");
         try (var executor = Executors.newVirtualThreadPerTaskExecutor()) {
@@ -98,7 +98,7 @@ public class DumpThreads {
      * Thread dump in JSON format.
      */
     @Test
-    public void testJson() throws Exception {
+    void testJson() throws Exception {
         var mbean = ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class);
         Path file = genOutputPath("json");
         try (var executor = Executors.newVirtualThreadPerTaskExecutor()) {
@@ -118,7 +118,7 @@ public class DumpThreads {
                 ZonedDateTime.parse(threadDump.time());
 
                 // test threadDump/runtimeVersion
-                assertEquals(threadDump.runtimeVersion(), Runtime.version().toString());
+                assertEquals(Runtime.version().toString(), threadDump.runtimeVersion());
 
                 // test root container
                 var rootContainer = threadDump.rootThreadContainer();
@@ -150,7 +150,7 @@ public class DumpThreads {
      * Test that dumpThreads throws if the output file already exists.
      */
     @Test
-    public void testFileAlreadyExsists() throws Exception {
+    void testFileAlreadyExsists() throws Exception {
         var mbean = ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class);
         String file = Files.createFile(genOutputPath("txt")).toString();
         assertThrows(FileAlreadyExistsException.class,
@@ -163,7 +163,7 @@ public class DumpThreads {
      * Test that dumpThreads throws if the file path is relative.
      */
     @Test
-    public void testRelativePath() throws Exception {
+    void testRelativePath() throws Exception {
         var mbean = ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class);
         assertThrows(IllegalArgumentException.class,
                 () -> mbean.dumpThreads("threads.txt", ThreadDumpFormat.TEXT_PLAIN));
@@ -175,7 +175,7 @@ public class DumpThreads {
      * Test that dumpThreads throws with null parameters.
      */
     @Test
-    public void testNull() throws Exception {
+    void testNull() throws Exception {
         var mbean = ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class);
         assertThrows(NullPointerException.class,
                 () -> mbean.dumpThreads(null, ThreadDumpFormat.TEXT_PLAIN));
diff --git a/test/jdk/java/lang/Thread/BuilderTest.java b/test/jdk/java/lang/Thread/BuilderTest.java
index f29986d9edf..0aaf247fed6 100644
--- a/test/jdk/java/lang/Thread/BuilderTest.java
+++ b/test/jdk/java/lang/Thread/BuilderTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,7 +25,7 @@
  * @test
  * @summary Unit test for Thread.Builder
  * @enablePreview
- * @run testng BuilderTest
+ * @run junit BuilderTest
  */
 
 import java.util.concurrent.*;
@@ -33,17 +33,17 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.locks.LockSupport;
 
-import org.testng.SkipException;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assumptions.*;
 
-public class BuilderTest {
+class BuilderTest {
 
     /**
      * Test Thread.ofPlatform to create platform threads.
      */
     @Test
-    public void testPlatformThread() throws Exception {
+    void testPlatformThread() throws Exception {
         Thread parent = Thread.currentThread();
         Thread.Builder.OfPlatform builder = Thread.ofPlatform();
 
@@ -94,7 +94,7 @@ public class BuilderTest {
      * Test Thread.ofVirtual to create virtual threads.
      */
     @Test
-    public void testVirtualThread() throws Exception {
+    void testVirtualThread() throws Exception {
         Thread parent = Thread.currentThread();
         Thread.Builder.OfVirtual builder = Thread.ofVirtual();
 
@@ -141,7 +141,7 @@ public class BuilderTest {
      * Test Thread.Builder.name.
      */
     @Test
-    public void testName1() {
+    void testName1() {
         Thread.Builder builder = Thread.ofPlatform().name("duke");
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -154,7 +154,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testName2() {
+    void testName2() {
         Thread.Builder builder = Thread.ofVirtual().name("duke");
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -167,7 +167,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testName3() {
+    void testName3() {
         Thread.Builder builder = Thread.ofPlatform().name("duke-", 100);
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -189,7 +189,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testName4() {
+    void testName4() {
         Thread.Builder builder = Thread.ofVirtual().name("duke-", 100);
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -214,7 +214,7 @@ public class BuilderTest {
      * Test Thread.Builder.OfPlatform.group.
      */
     @Test
-    public void testThreadGroup1() {
+    void testThreadGroup1() {
         ThreadGroup group = new ThreadGroup("groupies");
         Thread.Builder builder = Thread.ofPlatform().group(group);
 
@@ -240,9 +240,9 @@ public class BuilderTest {
     }
 
     @Test
-    public void testThreadGroup2() {
+    void testThreadGroup2() {
         ThreadGroup vgroup = Thread.ofVirtual().unstarted(() -> { }).getThreadGroup();
-        assertEquals(vgroup.getName(), "VirtualThreads");
+        assertEquals("VirtualThreads", vgroup.getName());
 
         Thread thread1 = Thread.ofVirtual().unstarted(() -> { });
         Thread thread2 = Thread.ofVirtual().start(LockSupport::park);
@@ -261,7 +261,7 @@ public class BuilderTest {
      * Test Thread.Builder.OfPlatform.priority.
      */
     @Test
-    public void testPriority1() {
+    void testPriority1() {
         int priority = Thread.currentThread().getPriority();
 
         Thread.Builder builder = Thread.ofPlatform();
@@ -275,7 +275,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testPriority2() {
+    void testPriority2() {
         int priority = Thread.MIN_PRIORITY;
 
         Thread.Builder builder = Thread.ofPlatform().priority(priority);
@@ -289,10 +289,9 @@ public class BuilderTest {
     }
 
     @Test
-    public void testPriority3() {
+    void testPriority3() {
         Thread currentThread = Thread.currentThread();
-        if (currentThread.isVirtual())
-            throw new SkipException("Main test is a virtual thread");
+        assumeFalse(currentThread.isVirtual(), "Main thread is a virtual thread");
 
         int maxPriority = currentThread.getThreadGroup().getMaxPriority();
         int priority = Math.min(maxPriority + 1, Thread.MAX_PRIORITY);
@@ -308,14 +307,14 @@ public class BuilderTest {
     }
 
     @Test
-    public void testPriority4() {
+    void testPriority4() {
         var builder = Thread.ofPlatform();
         assertThrows(IllegalArgumentException.class,
                      () -> builder.priority(Thread.MIN_PRIORITY - 1));
     }
 
     @Test
-    public void testPriority5() {
+    void testPriority5() {
         var builder = Thread.ofPlatform();
         assertThrows(IllegalArgumentException.class,
                      () -> builder.priority(Thread.MAX_PRIORITY + 1));
@@ -325,7 +324,7 @@ public class BuilderTest {
      * Test Thread.Builder.OfPlatform.daemon.
      */
     @Test
-    public void testDaemon1() {
+    void testDaemon1() {
         Thread.Builder builder = Thread.ofPlatform().daemon(false);
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -338,7 +337,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testDaemon2() {
+    void testDaemon2() {
         Thread.Builder builder = Thread.ofPlatform().daemon(true);
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -351,7 +350,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testDaemon3() {
+    void testDaemon3() {
         Thread.Builder builder = Thread.ofPlatform().daemon();
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -364,7 +363,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testDaemon4() {
+    void testDaemon4() {
         Thread.Builder builder = Thread.ofPlatform();
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -382,7 +381,7 @@ public class BuilderTest {
      * Test Thread.ofVirtual creates daemon threads.
      */
     @Test
-    public void testDaemon5() {
+    void testDaemon5() {
         Thread.Builder builder = Thread.ofVirtual();
 
         Thread thread1 = builder.unstarted(() -> { });
@@ -399,7 +398,7 @@ public class BuilderTest {
      * Test Thread.Builder.OfPlatform.stackSize.
      */
     @Test
-    public void testStackSize1() {
+    void testStackSize1() {
         Thread.Builder builder = Thread.ofPlatform().stackSize(1024*1024);
         Thread thread1 = builder.unstarted(() -> { });
         Thread thread2 = builder.start(() -> { });
@@ -407,7 +406,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testStackSize2() {
+    void testStackSize2() {
         Thread.Builder builder = Thread.ofPlatform().stackSize(0);
         Thread thread1 = builder.unstarted(() -> { });
         Thread thread2 = builder.start(() -> { });
@@ -415,7 +414,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testStackSize3() {
+    void testStackSize3() {
         var builder = Thread.ofPlatform();
         assertThrows(IllegalArgumentException.class, () -> builder.stackSize(-1));
     }
@@ -424,7 +423,7 @@ public class BuilderTest {
      * Test Thread.Builder.uncaughtExceptionHandler.
      */
     @Test
-    public void testUncaughtExceptionHandler1() throws Exception {
+    void testUncaughtExceptionHandler1() throws Exception {
         class FooException extends RuntimeException { }
         AtomicReference<Thread> threadRef = new AtomicReference<>();
         AtomicReference<Throwable> exceptionRef = new AtomicReference<>();
@@ -441,7 +440,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testUncaughtExceptionHandler2() throws Exception {
+    void testUncaughtExceptionHandler2() throws Exception {
         class FooException extends RuntimeException { }
         AtomicReference<Thread> threadRef = new AtomicReference<>();
         AtomicReference<Throwable> exceptionRef = new AtomicReference<>();
@@ -458,7 +457,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testUncaughtExceptionHandler3() throws Exception {
+    void testUncaughtExceptionHandler3() throws Exception {
         class FooException extends RuntimeException { }
         AtomicReference<Thread> threadRef = new AtomicReference<>();
         AtomicReference<Throwable> exceptionRef = new AtomicReference<>();
@@ -477,7 +476,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testUncaughtExceptionHandler4() throws Exception {
+    void testUncaughtExceptionHandler4() throws Exception {
         class FooException extends RuntimeException { }
         AtomicReference<Thread> threadRef = new AtomicReference<>();
         AtomicReference<Throwable> exceptionRef = new AtomicReference<>();
@@ -563,13 +562,13 @@ public class BuilderTest {
      * Test Thread.Builder creates threads that allow thread locals.
      */
     @Test
-    public void testThreadLocals1() throws Exception {
+    void testThreadLocals1() throws Exception {
         Thread.Builder builder = Thread.ofPlatform();
         testThreadLocals(builder);
     }
 
     @Test
-    public void testThreadLocals2() throws Exception {
+    void testThreadLocals2() throws Exception {
         Thread.Builder builder = Thread.ofVirtual();
         testThreadLocals(builder);
     }
@@ -579,7 +578,7 @@ public class BuilderTest {
      * thread locals.
      */
     @Test
-    public void testThreadLocals3() throws Exception {
+    void testThreadLocals3() throws Exception {
         Thread.Builder builder = Thread.ofPlatform();
 
         // disallow
@@ -592,7 +591,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testThreadLocals4() throws Exception {
+    void testThreadLocals4() throws Exception {
         Thread.Builder builder = Thread.ofVirtual();
 
         // disallow
@@ -646,7 +645,7 @@ public class BuilderTest {
 
         AtomicBoolean done = new AtomicBoolean();
         Runnable task = () -> {
-            assertTrue(INHERITED_LOCAL.get() == null);
+            assertNull(INHERITED_LOCAL.get());
             done.set(true);
         };
 
@@ -673,7 +672,7 @@ public class BuilderTest {
      * the initial values of inheritable thread locals.
      */
     @Test
-    public void testInheritedThreadLocals1() throws Exception {
+    void testInheritedThreadLocals1() throws Exception {
         Thread.Builder builder = Thread.ofPlatform();
         testInheritedThreadLocals(builder); // default
 
@@ -687,7 +686,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testInheritedThreadLocals2() throws Exception {
+    void testInheritedThreadLocals2() throws Exception {
         Thread.Builder builder = Thread.ofVirtual();
         testInheritedThreadLocals(builder); // default
 
@@ -701,7 +700,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testInheritedThreadLocals3() throws Exception {
+    void testInheritedThreadLocals3() throws Exception {
         Thread.Builder builder = Thread.ofPlatform();
 
         // thread locals not allowed
@@ -721,7 +720,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testInheritedThreadLocals4() throws Exception {
+    void testInheritedThreadLocals4() throws Exception {
         Thread.Builder builder = Thread.ofVirtual();
 
         // thread locals not allowed
@@ -824,7 +823,7 @@ public class BuilderTest {
      * the thread context class loader.
      */
     @Test
-    public void testContextClassLoader1() throws Exception {
+    void testContextClassLoader1() throws Exception {
         Thread.Builder builder = Thread.ofPlatform();
         testInheritContextClassLoader(builder); // default
 
@@ -838,7 +837,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testContextClassLoader2() throws Exception {
+    void testContextClassLoader2() throws Exception {
         Thread.Builder builder = Thread.ofVirtual();
         testInheritContextClassLoader(builder); // default
 
@@ -852,7 +851,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testContextClassLoader3() throws Exception {
+    void testContextClassLoader3() throws Exception {
         Thread.Builder builder = Thread.ofPlatform();
 
         // thread locals not allowed
@@ -872,7 +871,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testContextClassLoader4() throws Exception {
+    void testContextClassLoader4() throws Exception {
         Thread.Builder builder = Thread.ofVirtual();
 
         // thread locals not allowed
@@ -895,7 +894,7 @@ public class BuilderTest {
      * Test NullPointerException.
      */
     @Test
-    public void testNulls1() {
+    void testNulls1() {
         Thread.Builder.OfPlatform builder = Thread.ofPlatform();
         assertThrows(NullPointerException.class, () -> builder.group(null));
         assertThrows(NullPointerException.class, () -> builder.name(null));
@@ -906,7 +905,7 @@ public class BuilderTest {
     }
 
     @Test
-    public void testNulls2() {
+    void testNulls2() {
         Thread.Builder builder = Thread.ofVirtual();
         assertThrows(NullPointerException.class, () -> builder.name(null));
         assertThrows(NullPointerException.class, () -> builder.name(null, 0));
diff --git a/test/jdk/java/lang/Thread/JoinWithDuration.java b/test/jdk/java/lang/Thread/JoinWithDuration.java
index d5c769ec1cf..0eae0daeb78 100644
--- a/test/jdk/java/lang/Thread/JoinWithDuration.java
+++ b/test/jdk/java/lang/Thread/JoinWithDuration.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -24,22 +24,22 @@
 /**
  * @test
  * @summary Test Thread.join(Duration)
- * @run testng JoinWithDuration
+ * @run junit JoinWithDuration
  */
 
 import java.time.Duration;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.LockSupport;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class JoinWithDuration {
+class JoinWithDuration {
     /**
      * Test join on unstarted thread.
      */
     @Test
-    public void testJoinOnUnstartedThread() {
+    void testJoinOnUnstartedThread() {
         var thread = new Thread(() -> { });
         assertThrows(IllegalThreadStateException.class,
                 () -> thread.join(Duration.ofNanos(-100)));
@@ -53,7 +53,7 @@ public class JoinWithDuration {
      * Test join on thread that does not terminate while waiting.
      */
     @Test
-    public void testJoinOnRunningThread() throws Exception {
+    void testJoinOnRunningThread() throws Exception {
         var thread = new Thread(LockSupport::park);
         thread.start();
         try {
@@ -76,7 +76,7 @@ public class JoinWithDuration {
      * Test join on thread that terminates while waiting.
      */
     @Test
-    public void testJoinOnTerminatingThread() throws Exception {
+    void testJoinOnTerminatingThread() throws Exception {
         var thread = new Thread(() -> {
             try {
                 Thread.sleep(50);
@@ -90,7 +90,7 @@ public class JoinWithDuration {
      * Test join on terminated thread.
      */
     @Test
-    public void testJoinOnTerminatedThread() throws Exception {
+    void testJoinOnTerminatedThread() throws Exception {
         var thread = new Thread(() -> { });
         thread.start();
         thread.join();
@@ -103,7 +103,7 @@ public class JoinWithDuration {
      * Test invoking join with interrupt status set.
      */
     @Test
-    public void testJoinWithInterruptStatusSet() throws Exception {
+    void testJoinWithInterruptStatusSet() throws Exception {
         var thread = new Thread(LockSupport::park);
         thread.start();
         Thread.currentThread().interrupt();
@@ -122,8 +122,8 @@ public class JoinWithDuration {
      * Test interrupting join.
      */
     @Test
-    public void testInterruptJoin() throws Exception {
-        // schedule current thread to interrupted after 1s
+    void testInterruptJoin() throws Exception {
+        // schedule current thread to be interrupted after 1s
         Thread targetThread = Thread.currentThread();
         Thread wakerThread = new Thread(() -> {
             try {
@@ -144,7 +144,9 @@ public class JoinWithDuration {
             // interrupt status should be cleared
             assertFalse(thread.isInterrupted());
         } finally {
-            wakerThread.interrupt();
+            LockSupport.unpark(thread);
+            thread.join();
+            wakerThread.join();
         }
     }
 
@@ -152,7 +154,7 @@ public class JoinWithDuration {
      * Test join on current thread.
      */
     @Test
-    public void testJoinSelf() throws Exception {
+    void testJoinSelf() throws Exception {
         Thread thread = Thread.currentThread();
 
         assertFalse(thread.join(Duration.ofNanos(-100)));
@@ -169,7 +171,7 @@ public class JoinWithDuration {
      * Test join(null).
      */
     @Test
-    public void testJoinNull() throws Exception {
+    void testJoinNull() throws Exception {
         var thread = new Thread(LockSupport::park);
 
         // unstarted
diff --git a/test/jdk/java/lang/Thread/SleepWithDuration.java b/test/jdk/java/lang/Thread/SleepWithDuration.java
index d19f7713647..4db64957f64 100644
--- a/test/jdk/java/lang/Thread/SleepWithDuration.java
+++ b/test/jdk/java/lang/Thread/SleepWithDuration.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -24,22 +24,22 @@
 /**
  * @test
  * @summary Test Thread.sleep(Duration)
- * @run testng SleepWithDuration
+ * @run junit SleepWithDuration
  */
 
 import java.time.Duration;
 import java.util.concurrent.TimeUnit;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class SleepWithDuration {
+class SleepWithDuration {
 
     /**
      * Basic test for sleep(Duration).
      */
     @Test
-    public void testSleep() throws Exception {
+    void testSleep() throws Exception {
         // sleep for 2 seconds
         long start = millisTime();
         Thread.sleep(Duration.ofMillis(2000));
@@ -56,7 +56,7 @@ public class SleepWithDuration {
      * Test Thread.sleep with interrupt status set.
      */
     @Test
-    public void testSleepWithInterruptStatusSet() throws Exception {
+    void testSleepWithInterruptStatusSet() throws Exception {
         Thread.currentThread().interrupt();
         try {
             Thread.sleep(Duration.ofNanos(0));
@@ -78,8 +78,8 @@ public class SleepWithDuration {
      * Test interrupting Thread.sleep.
      */
     @Test
-    public void testInterruptSleep() throws Exception {
-        // schedule current thread to interrupted after 1s
+    void testInterruptSleep() throws Exception {
+        // schedule current thread to be interrupted after 1s
         Thread targetThread = Thread.currentThread();
         Thread wakerThread = new Thread(() -> {
             try {
@@ -97,7 +97,7 @@ public class SleepWithDuration {
             // interrupt status should be cleared
             assertFalse(Thread.interrupted());
         } finally {
-            wakerThread.interrupt();
+            wakerThread.join();
         }
     }
 
diff --git a/test/jdk/java/lang/Thread/UncaughtExceptionsTest.java b/test/jdk/java/lang/Thread/UncaughtExceptionsTest.java
index 0c4851a4fc8..e53c370e7f7 100644
--- a/test/jdk/java/lang/Thread/UncaughtExceptionsTest.java
+++ b/test/jdk/java/lang/Thread/UncaughtExceptionsTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -21,10 +21,14 @@
  * questions.
  */
 
+import java.util.stream.Stream;
+
 import jdk.test.lib.process.OutputAnalyzer;
 import jdk.test.lib.process.ProcessTools;
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.jupiter.params.provider.Arguments;
 
 import static java.lang.System.err;
 import static java.lang.System.out;
@@ -36,35 +40,50 @@ import static java.lang.System.out;
  * @author Martin Buchholz
  * @library /test/lib
  * @build jdk.test.lib.process.*
- * @run testng UncaughtExceptionsTest
+ * @run junit UncaughtExceptionsTest
  */
-public class UncaughtExceptionsTest {
+class UncaughtExceptionsTest {
 
-    @DataProvider
-    public Object[][] testCases() {
-        return new Object[][] {
-            new Object[] { "ThreadIsDeadAfterJoin",
-                           0,
-                           UncaughtExitSimulator.EXPECTED_RESULT,
-                           "Exception in thread \"Thread-\\d+\".*simulateUncaughtExitEvent"
-            },
-            new Object[] {
-                            "MainThreadAbruptTermination",
-                            1,
-                            UncaughtExitSimulator.EXPECTED_RESULT,
-                            "Exception in thread \"main\".*simulateUncaughtExitEvent"
-            },
-            new Object[] { "MainThreadNormalTermination", 0, UncaughtExitSimulator.EXPECTED_RESULT, ""},
-            new Object[] { "DefaultUncaughtExceptionHandlerOnMainThread", 1, UncaughtExitSimulator.EXPECTED_RESULT, "" },
-            new Object[] { "DefaultUncaughtExceptionHandlerOnMainThreadOverride", 1, UncaughtExitSimulator.EXPECTED_RESULT, "" },
-            new Object[] { "DefaultUncaughtExceptionHandlerOnNonMainThreadOverride", 0, UncaughtExitSimulator.EXPECTED_RESULT, "" },
-            new Object[] { "DefaultUncaughtExceptionHandlerOnNonMainThread", 0, UncaughtExitSimulator.EXPECTED_RESULT, "" },
-            new Object[] { "ThreadGroupUncaughtExceptionHandlerOnNonMainThread", 0, UncaughtExitSimulator.EXPECTED_RESULT, "" }
-        };
+    private static Stream<Arguments> testCases() {
+        return Stream.of(
+            Arguments.of("ThreadIsDeadAfterJoin",
+                         0,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         "Exception in thread \"Thread-\\d+\".*simulateUncaughtExitEvent"),
+            Arguments.of("MainThreadAbruptTermination",
+                         1,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         "Exception in thread \"main\".*simulateUncaughtExitEvent"),
+            Arguments.of("MainThreadNormalTermination",
+                         0,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         ""),
+            Arguments.of("DefaultUncaughtExceptionHandlerOnMainThread",
+                         1,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         ""),
+            Arguments.of("DefaultUncaughtExceptionHandlerOnMainThreadOverride",
+                         1,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         ""),
+            Arguments.of("DefaultUncaughtExceptionHandlerOnNonMainThreadOverride",
+                         0,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         ""),
+            Arguments.of("DefaultUncaughtExceptionHandlerOnNonMainThread",
+                         0,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         ""),
+            Arguments.of("ThreadGroupUncaughtExceptionHandlerOnNonMainThread",
+                         0,
+                         UncaughtExitSimulator.EXPECTED_RESULT,
+                         "")
+        );
     }
 
-    @Test(dataProvider = "testCases")
-    public void test(String className, int exitValue, String stdOutMatch, String stdErrMatch) throws Throwable {
+    @ParameterizedTest
+    @MethodSource("testCases")
+    void test(String className, int exitValue, String stdOutMatch, String stdErrMatch) throws Throwable {
         String cmd = "UncaughtExitSimulator$" + className;
         ProcessBuilder processBuilder = ProcessTools.createJavaProcessBuilder(cmd);
         OutputAnalyzer outputAnalyzer = ProcessTools.executeCommand(processBuilder);
@@ -91,7 +110,9 @@ class UncaughtExitSimulator extends Thread implements Runnable {
 
     final static String EXPECTED_RESULT = "OK";
 
-    public static void throwRuntimeException() { throw new RuntimeException("simulateUncaughtExitEvent"); }
+    public static void throwRuntimeException() {
+        throw new RuntimeException("simulateUncaughtExitEvent");
+    }
 
     public void run() { throwRuntimeException(); }
 
diff --git a/test/jdk/java/lang/Thread/virtual/Collectable.java b/test/jdk/java/lang/Thread/virtual/Collectable.java
index 4da3a003d9a..9003c0d6fa0 100644
--- a/test/jdk/java/lang/Thread/virtual/Collectable.java
+++ b/test/jdk/java/lang/Thread/virtual/Collectable.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,22 +25,22 @@
  * @test
  * @summary Test that virtual threads are GC'ed
  * @enablePreview
- * @run testng Collectable
+ * @run junit Collectable
  */
 
 import java.lang.ref.WeakReference;
 import java.util.concurrent.locks.LockSupport;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class Collectable {
+class Collectable {
 
     /**
      * Test that an unstarted virtual thread can be GC"ed.
      */
     @Test
-    public void testUnstartedThread() {
+    void testUnstartedThread() {
         var thread = Thread.ofVirtual().unstarted(() -> { });
         var ref = new WeakReference<>(thread);
         thread = null;
@@ -51,7 +51,7 @@ public class Collectable {
      * Test that a terminated virtual thread can be GC'ed.
      */
     @Test
-    public void testTerminatedThread() throws Exception {
+    void testTerminatedThread() throws Exception {
         var thread = Thread.ofVirtual().start(() -> { });
         thread.join();
         var ref = new WeakReference<>(thread);
diff --git a/test/jdk/java/lang/Thread/virtual/CustomScheduler.java b/test/jdk/java/lang/Thread/virtual/CustomScheduler.java
index f198b16676f..edd6924bb30 100644
--- a/test/jdk/java/lang/Thread/virtual/CustomScheduler.java
+++ b/test/jdk/java/lang/Thread/virtual/CustomScheduler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
  * @requires vm.continuations
  * @modules java.base/java.lang:+open
  * @enablePreview
- * @run testng CustomScheduler
+ * @run junit CustomScheduler
  */
 
 import java.lang.reflect.Field;
@@ -39,57 +39,57 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.locks.LockSupport;
 
-import org.testng.SkipException;
-import org.testng.annotations.BeforeClass;
-import org.testng.annotations.AfterClass;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.AfterAll;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assumptions.*;
 
-public class CustomScheduler {
+class CustomScheduler {
     private static final Executor DEFAULT_SCHEDULER = defaultScheduler();
-    private static ExecutorService SCHEDULER_1;
-    private static ExecutorService SCHEDULER_2;
+    private static ExecutorService scheduler1;
+    private static ExecutorService scheduler2;
 
-    @BeforeClass
-    public void setup() {
-        SCHEDULER_1 = Executors.newFixedThreadPool(1);
-        SCHEDULER_2 = Executors.newFixedThreadPool(1);
+    @BeforeAll
+    static void setup() {
+        scheduler1 = Executors.newFixedThreadPool(1);
+        scheduler2 = Executors.newFixedThreadPool(1);
     }
 
-    @AfterClass
-    public void shutdown() {
-        SCHEDULER_1.shutdown();
-        SCHEDULER_2.shutdown();
+    @AfterAll
+    static void shutdown() {
+        scheduler1.shutdown();
+        scheduler2.shutdown();
     }
 
     /**
      * Test platform thread creating a virtual thread that uses a custom scheduler.
      */
     @Test
-    public void testCustomScheduler1() throws Exception {
+    void testCustomScheduler1() throws Exception {
         AtomicReference<Executor> ref = new AtomicReference<>();
-        ThreadBuilders.virtualThreadBuilder(SCHEDULER_1).start(() -> {
+        ThreadBuilders.virtualThreadBuilder(scheduler1).start(() -> {
             ref.set(scheduler(Thread.currentThread()));
         }).join();
-        assertTrue(ref.get() == SCHEDULER_1);
+        assertTrue(ref.get() == scheduler1);
     }
 
     /**
      * Test virtual thread creating a virtual thread that uses a custom scheduler.
      */
     @Test
-    public void testCustomScheduler2() throws Exception {
+    void testCustomScheduler2() throws Exception {
         AtomicReference<Executor> ref = new AtomicReference<>();
         Thread.ofVirtual().start(() -> {
             try {
-                ThreadBuilders.virtualThreadBuilder(SCHEDULER_1).start(() -> {
+                ThreadBuilders.virtualThreadBuilder(scheduler1).start(() -> {
                     ref.set(scheduler(Thread.currentThread()));
                 }).join();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }).join();
-        assertTrue(ref.get() == SCHEDULER_1);
+        assertTrue(ref.get() == scheduler1);
     }
 
     /**
@@ -97,9 +97,9 @@ public class CustomScheduler {
      * The scheduler should be inherited.
      */
     @Test
-    public void testCustomScheduler3() throws Exception {
+    void testCustomScheduler3() throws Exception {
         AtomicReference<Executor> ref = new AtomicReference<>();
-        ThreadBuilders.virtualThreadBuilder(SCHEDULER_1).start(() -> {
+        ThreadBuilders.virtualThreadBuilder(scheduler1).start(() -> {
             try {
                 Thread.ofVirtual().start(() -> {
                     ref.set(scheduler(Thread.currentThread()));
@@ -108,7 +108,7 @@ public class CustomScheduler {
                 e.printStackTrace();
             }
         }).join();
-        assertTrue(ref.get() == SCHEDULER_1);
+        assertTrue(ref.get() == scheduler1);
     }
 
     /**
@@ -116,25 +116,25 @@ public class CustomScheduler {
      * that uses a different custom scheduler.
      */
     @Test
-    public void testCustomScheduler4() throws Exception {
+    void testCustomScheduler4() throws Exception {
         AtomicReference<Executor> ref = new AtomicReference<>();
-        ThreadBuilders.virtualThreadBuilder(SCHEDULER_1).start(() -> {
+        ThreadBuilders.virtualThreadBuilder(scheduler1).start(() -> {
             try {
-                ThreadBuilders.virtualThreadBuilder(SCHEDULER_2).start(() -> {
+                ThreadBuilders.virtualThreadBuilder(scheduler2).start(() -> {
                     ref.set(scheduler(Thread.currentThread()));
                 }).join();
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }).join();
-        assertTrue(ref.get() == SCHEDULER_2);
+        assertTrue(ref.get() == scheduler2);
     }
 
     /**
      * Test running task on a virtual thread, should thrown WrongThreadException.
      */
     @Test
-    public void testBadCarrier() {
+    void testBadCarrier() {
         Executor scheduler = (task) -> {
             var exc = new AtomicReference<Throwable>();
             try {
@@ -160,10 +160,9 @@ public class CustomScheduler {
      * carrier thread when the task completes.
      */
     @Test
-    public void testParkWithInterruptSet() {
+    void testParkWithInterruptSet() {
         Thread carrier = Thread.currentThread();
-        if (carrier.isVirtual())
-            throw new SkipException("Main test is a virtual thread");
+        assumeFalse(carrier.isVirtual(), "Main thread is a virtual thread");
         try {
             var builder = ThreadBuilders.virtualThreadBuilder(Runnable::run);
             Thread vthread = builder.start(() -> {
@@ -182,10 +181,9 @@ public class CustomScheduler {
      * the carrier thread when the task completes.
      */
     @Test
-    public void testTerminateWithInterruptSet() {
+    void testTerminateWithInterruptSet() {
         Thread carrier = Thread.currentThread();
-        if (carrier.isVirtual())
-            throw new SkipException("Main test is a virtual thread");
+        assumeFalse(carrier.isVirtual(), "Main thread is a virtual thread");
         try {
             var builder = ThreadBuilders.virtualThreadBuilder(Runnable::run);
             Thread vthread = builder.start(() -> {
@@ -202,9 +200,8 @@ public class CustomScheduler {
      * Test running task with the carrier interrupt status set.
      */
     @Test
-    public void testRunWithInterruptSet() throws Exception {
-        if (Thread.currentThread().isVirtual())
-            throw new SkipException("Main test is a virtual thread");
+    void testRunWithInterruptSet() throws Exception {
+        assumeFalse(Thread.currentThread().isVirtual(), "Main thread is a virtual thread");
         Executor scheduler = (task) -> {
             Thread.currentThread().interrupt();
             task.run();
diff --git a/test/jdk/java/lang/Thread/virtual/GetStackTrace.java b/test/jdk/java/lang/Thread/virtual/GetStackTrace.java
index 1518adc2741..f8e1f1d816c 100644
--- a/test/jdk/java/lang/Thread/virtual/GetStackTrace.java
+++ b/test/jdk/java/lang/Thread/virtual/GetStackTrace.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,9 +25,10 @@
  * @test
  * @summary Test Thread.getStackTrace to examine the stack trace of a virtual
  *     thread and its carrier
- * @modules java.base/java.lang:+open
+ * @requires vm.continuations
  * @enablePreview
- * @run testng GetStackTrace
+ * @modules java.base/java.lang:+open
+ * @run main GetStackTrace
  */
 
 import java.util.Objects;
diff --git a/test/jdk/java/lang/Thread/virtual/HoldsLock.java b/test/jdk/java/lang/Thread/virtual/HoldsLock.java
index 016cc736d2e..80da73504b0 100644
--- a/test/jdk/java/lang/Thread/virtual/HoldsLock.java
+++ b/test/jdk/java/lang/Thread/virtual/HoldsLock.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
  * @requires vm.continuations
  * @modules java.base/java.lang:+open
  * @enablePreview
- * @run testng HoldsLock
+ * @run junit HoldsLock
  */
 
 /**
@@ -36,7 +36,7 @@
  * @requires vm.continuations & vm.debug
  * @modules java.base/java.lang:+open
  * @enablePreview
- * @run testng/othervm -XX:+UseHeavyMonitors HoldsLock
+ * @run junit/othervm -XX:+UseHeavyMonitors HoldsLock
  */
 
 import java.lang.management.LockInfo;
@@ -52,15 +52,17 @@ import java.util.concurrent.RejectedExecutionException;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.atomic.AtomicReference;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Disabled;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class HoldsLock {
+class HoldsLock {
     static final Object LOCK1 = new Object();
     static final Object LOCK2 = new Object();
 
-    @Test(enabled=false) // JDK-8281642
-    public void testHoldsLock() throws Exception {
+    @Disabled("JDK-8281642")
+    @Test
+    void testHoldsLock() throws Exception {
         var q = new ArrayBlockingQueue<Runnable>(5);
 
         Thread carrier = Thread.ofPlatform().start(() -> {
@@ -85,7 +87,7 @@ public class HoldsLock {
     }
 
     @Test
-    public void testThreadInfo() throws Exception {
+    void testThreadInfo() throws Exception {
         var q = new ArrayBlockingQueue<Runnable>(5);
 
         Thread carrier = spawnCarrier(q);
@@ -123,10 +125,10 @@ public class HoldsLock {
 
             if (tid == carrierId) {
                 // Carrier is WAITING on vthread
-                assertEquals(info.getThreadState(), Thread.State.WAITING);
-                assertEquals(info.getLockInfo().getClassName(), vthread.getClass().getName());
-                assertEquals(info.getLockInfo().getIdentityHashCode(), System.identityHashCode(vthread));
-                assertEquals(info.getLockOwnerId(), vthreadId);
+                assertTrue(info.getThreadState() == Thread.State.WAITING);
+                assertEquals(vthread.getClass().getName(), info.getLockInfo().getClassName());
+                assertTrue(info.getLockInfo().getIdentityHashCode() == System.identityHashCode(vthread));
+                assertTrue(info.getLockOwnerId() == vthreadId);
                 foundCarrier = true;
             }
         }
diff --git a/test/jdk/java/lang/Thread/virtual/JfrEvents.java b/test/jdk/java/lang/Thread/virtual/JfrEvents.java
index 87f9f420062..72afb229cb3 100644
--- a/test/jdk/java/lang/Thread/virtual/JfrEvents.java
+++ b/test/jdk/java/lang/Thread/virtual/JfrEvents.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
  * @requires vm.continuations
  * @modules jdk.jfr java.base/java.lang:+open
  * @enablePreview
- * @run testng/othervm JfrEvents
+ * @run junit/othervm JfrEvents
  */
 
 import java.io.IOException;
@@ -48,17 +48,17 @@ import jdk.jfr.Recording;
 import jdk.jfr.consumer.RecordedEvent;
 import jdk.jfr.consumer.RecordingFile;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class JfrEvents {
+class JfrEvents {
     private static final Object lock = new Object();
 
     /**
      * Test jdk.VirtualThreadStart and jdk.VirtualThreadEnd events.
      */
     @Test
-    public void testVirtualThreadStartAndEnd() throws Exception {
+    void testVirtualThreadStartAndEnd() throws Exception {
         try (Recording recording = new Recording()) {
             recording.enable("jdk.VirtualThreadStart");
             recording.enable("jdk.VirtualThreadEnd");
@@ -89,7 +89,7 @@ public class JfrEvents {
      * Test jdk.VirtualThreadPinned event.
      */
     @Test
-    public void testVirtualThreadPinned() throws Exception {
+    void testVirtualThreadPinned() throws Exception {
         try (Recording recording = new Recording()) {
             recording.enable("jdk.VirtualThreadPinned")
                      .withThreshold(Duration.ofMillis(500));
@@ -126,7 +126,7 @@ public class JfrEvents {
      * Test jdk.VirtualThreadSubmitFailed event.
      */
     @Test
-    public void testVirtualThreadSubmitFailed() throws Exception {
+    void testVirtualThreadSubmitFailed() throws Exception {
         try (Recording recording = new Recording()) {
             recording.enable("jdk.VirtualThreadSubmitFailed");
 
diff --git a/test/jdk/java/lang/Thread/virtual/Locking.java b/test/jdk/java/lang/Thread/virtual/Locking.java
index 76c82201500..e70ee867f5e 100644
--- a/test/jdk/java/lang/Thread/virtual/Locking.java
+++ b/test/jdk/java/lang/Thread/virtual/Locking.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,7 +26,7 @@
  * @summary Test virtual threads using java.util.concurrent locks
  * @library /test/lib
  * @enablePreview
- * @run testng Locking
+ * @run junit Locking
  */
 
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -34,16 +34,16 @@ import java.util.concurrent.locks.LockSupport;
 import java.util.concurrent.locks.ReentrantLock;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class Locking {
+class Locking {
 
     /**
      * Test lock/unlock.
      */
     @Test
-    public void testReentrantLock1() throws Exception {
+    void testReentrantLock1() throws Exception {
         VThreadRunner.run(() -> {
             ReentrantLock lock = new ReentrantLock();
             assertFalse(lock.isHeldByCurrentThread());
@@ -58,7 +58,7 @@ public class Locking {
      * Test tryLock/unlock.
      */
     @Test
-    public void testReentrantLock2() throws Exception {
+    void testReentrantLock2() throws Exception {
         VThreadRunner.run(() -> {
             ReentrantLock lock = new ReentrantLock();
             assertFalse(lock.isHeldByCurrentThread());
@@ -74,7 +74,7 @@ public class Locking {
      * Test lock/lock/unlock/unlock.
      */
     @Test
-    public void testReentrantLock3() throws Exception {
+    void testReentrantLock3() throws Exception {
         VThreadRunner.run(() -> {
             ReentrantLock lock = new ReentrantLock();
             assertFalse(lock.isHeldByCurrentThread());
@@ -98,7 +98,7 @@ public class Locking {
      * Test locked by platform thread, virtual thread tries to lock.
      */
     @Test
-    public void testReentrantLock4() throws Exception {
+    void testReentrantLock4() throws Exception {
         ReentrantLock lock = new ReentrantLock();
         var holdsLock = new AtomicBoolean();
 
@@ -136,7 +136,7 @@ public class Locking {
      * Test locked by virtual thread, platform thread tries to lock.
      */
     @Test
-    public void testReentrantLock5() throws Exception {
+    void testReentrantLock5() throws Exception {
         ReentrantLock lock = new ReentrantLock();
         var thread = Thread.ofVirtual().start(() -> {
             lock.lock();
@@ -170,7 +170,7 @@ public class Locking {
      * Test locked by virtual thread, another virtual thread tries to lock.
      */
     @Test
-    public void testReentrantLock6() throws Exception {
+    void testReentrantLock6() throws Exception {
         ReentrantLock lock = new ReentrantLock();
         var thread1 = Thread.ofVirtual().start(() -> {
             lock.lock();
diff --git a/test/jdk/java/lang/Thread/virtual/ParkWithFixedThreadPool.java b/test/jdk/java/lang/Thread/virtual/ParkWithFixedThreadPool.java
index 866d9bf24d7..b54135d9cc7 100644
--- a/test/jdk/java/lang/Thread/virtual/ParkWithFixedThreadPool.java
+++ b/test/jdk/java/lang/Thread/virtual/ParkWithFixedThreadPool.java
@@ -27,17 +27,15 @@
  * @requires vm.continuations
  * @modules java.base/java.lang:+open
  * @enablePreview
- * @run testng ParkWithFixedThreadPool
+ * @run main ParkWithFixedThreadPool
  */
+
 import java.util.concurrent.*;
 import java.util.concurrent.atomic.*;
 import java.util.concurrent.locks.LockSupport;
-import static org.testng.Assert.*;
-import org.testng.annotations.Test;
 
 public class ParkWithFixedThreadPool {
-    @Test
-    public static void multipleThreadPoolParkTest() throws Exception {
+    public static void main(String[] args) throws Exception {
         try (ExecutorService scheduler = Executors.newFixedThreadPool(8)) {
             int vthreadCount = 300;
             Thread[] vthreads = new Thread[vthreadCount];
diff --git a/test/jdk/java/lang/Thread/virtual/Parking.java b/test/jdk/java/lang/Thread/virtual/Parking.java
index 3e1558cfc7d..b4f70232ce1 100644
--- a/test/jdk/java/lang/Thread/virtual/Parking.java
+++ b/test/jdk/java/lang/Thread/virtual/Parking.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,7 +26,7 @@
  * @summary Test virtual threads using park/unpark
  * @library /test/lib
  * @enablePreview
- * @run testng Parking
+ * @run junit Parking
  */
 
 import java.time.Duration;
@@ -34,18 +34,17 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.LockSupport;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.SkipException;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class Parking {
+class Parking {
     private static final Object lock = new Object();
 
     /**
      * Park, unparked by platform thread.
      */
     @Test
-    public void testPark1() throws Exception {
+    void testPark1() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         Thread.sleep(1000); // give time for virtual thread to park
         LockSupport.unpark(thread);
@@ -56,7 +55,7 @@ public class Parking {
      * Park, unparked by virtual thread.
      */
     @Test
-    public void testPark2() throws Exception {
+    void testPark2() throws Exception {
         var thread1 = Thread.ofVirtual().start(LockSupport::park);
         Thread.sleep(1000); // give time for virtual thread to park
         var thread2 = Thread.ofVirtual().start(() -> LockSupport.unpark(thread1));
@@ -68,7 +67,7 @@ public class Parking {
      * Park while holding monitor, unparked by platform thread.
      */
     @Test
-    public void testPark3() throws Exception {
+    void testPark3() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             synchronized (lock) {
                 LockSupport.park();
@@ -83,15 +82,15 @@ public class Parking {
      * Park with native frame on stack.
      */
     @Test
-    public void testPark4() throws Exception {
-        throw new SkipException("Not implemented");
+    void testPark4() throws Exception {
+        // not implemented
     }
 
     /**
      * Unpark before park.
      */
     @Test
-    public void testPark5() throws Exception {
+    void testPark5() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             LockSupport.unpark(Thread.currentThread());
             LockSupport.park();
@@ -103,7 +102,7 @@ public class Parking {
      * 2 x unpark before park.
      */
     @Test
-    public void testPark6() throws Exception {
+    void testPark6() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             Thread me = Thread.currentThread();
             LockSupport.unpark(me);
@@ -120,7 +119,7 @@ public class Parking {
      * 2 x park and unpark by platform thread.
      */
     @Test
-    public void testPark7() throws Exception {
+    void testPark7() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             LockSupport.park();
             LockSupport.park();
@@ -142,7 +141,7 @@ public class Parking {
      * Park with interrupt status set.
      */
     @Test
-    public void testPark8() throws Exception {
+    void testPark8() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             t.interrupt();
@@ -155,7 +154,7 @@ public class Parking {
      * Thread interrupt when parked.
      */
     @Test
-    public void testPark9() throws Exception {
+    void testPark9() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             scheduleInterrupt(t, 1000);
@@ -169,7 +168,7 @@ public class Parking {
      * Park while holding monitor and with interrupt status set.
      */
     @Test
-    public void testPark10() throws Exception {
+    void testPark10() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             t.interrupt();
@@ -184,7 +183,7 @@ public class Parking {
      * Thread interrupt when parked while holding monitor
      */
     @Test
-    public void testPark11() throws Exception {
+    void testPark11() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             scheduleInterrupt(t, 1000);
@@ -200,7 +199,7 @@ public class Parking {
      * parkNanos(-1) completes immediately
      */
     @Test
-    public void testParkNanos1() throws Exception {
+    void testParkNanos1() throws Exception {
         VThreadRunner.run(() -> LockSupport.parkNanos(-1));
     }
 
@@ -208,7 +207,7 @@ public class Parking {
      * parkNanos(0) completes immediately
      */
     @Test
-    public void testParkNanos2() throws Exception {
+    void testParkNanos2() throws Exception {
         VThreadRunner.run(() -> LockSupport.parkNanos(0));
     }
 
@@ -216,7 +215,7 @@ public class Parking {
      * parkNanos(1000ms) parks thread.
      */
     @Test
-    public void testParkNanos3() throws Exception {
+    void testParkNanos3() throws Exception {
         VThreadRunner.run(() -> {
             // park for 1000ms
             long nanos = TimeUnit.NANOSECONDS.convert(1000, TimeUnit.MILLISECONDS);
@@ -234,7 +233,7 @@ public class Parking {
      * Park with parkNanos, unparked by platform thread.
      */
     @Test
-    public void testParkNanos4() throws Exception {
+    void testParkNanos4() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             long nanos = TimeUnit.NANOSECONDS.convert(1, TimeUnit.DAYS);
             LockSupport.parkNanos(nanos);
@@ -248,7 +247,7 @@ public class Parking {
      * Park with parkNanos, unparked by virtual thread.
      */
     @Test
-    public void testParkNanos5() throws Exception {
+    void testParkNanos5() throws Exception {
         var thread1 = Thread.ofVirtual().start(() -> {
             long nanos = TimeUnit.NANOSECONDS.convert(1, TimeUnit.DAYS);
             LockSupport.parkNanos(nanos);
@@ -263,7 +262,7 @@ public class Parking {
      * Unpark before parkNanos.
      */
     @Test
-    public void testParkNanos6() throws Exception {
+    void testParkNanos6() throws Exception {
         VThreadRunner.run(() -> {
             LockSupport.unpark(Thread.currentThread());
             long nanos = TimeUnit.NANOSECONDS.convert(1, TimeUnit.DAYS);
@@ -275,7 +274,7 @@ public class Parking {
      * Unpark before parkNanos(0), should consume parking permit.
      */
     @Test
-    public void testParkNanos7() throws Exception {
+    void testParkNanos7() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             LockSupport.unpark(Thread.currentThread());
             LockSupport.parkNanos(0);  // should consume parking permit
@@ -291,7 +290,7 @@ public class Parking {
      * Park with parkNanos and interrupt status set.
      */
     @Test
-    public void testParkNanos8() throws Exception {
+    void testParkNanos8() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             t.interrupt();
@@ -304,7 +303,7 @@ public class Parking {
      * Thread interrupt when parked in parkNanos.
      */
     @Test
-    public void testParkNanos9() throws Exception {
+    void testParkNanos9() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             scheduleInterrupt(t, 1000);
@@ -318,7 +317,7 @@ public class Parking {
      * Park with parkNanos while holding monitor and with interrupt status set.
      */
     @Test
-    public void testParkNanos10() throws Exception {
+    void testParkNanos10() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             t.interrupt();
@@ -333,7 +332,7 @@ public class Parking {
      * Thread interrupt when parked in parkNanos and while holding monitor.
      */
     @Test
-    public void testParkNanos11() throws Exception {
+    void testParkNanos11() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             scheduleInterrupt(t, 1000);
diff --git a/test/jdk/java/lang/Thread/virtual/PreviewFeaturesNotEnabled.java b/test/jdk/java/lang/Thread/virtual/PreviewFeaturesNotEnabled.java
index 12650d14643..083322e9904 100644
--- a/test/jdk/java/lang/Thread/virtual/PreviewFeaturesNotEnabled.java
+++ b/test/jdk/java/lang/Thread/virtual/PreviewFeaturesNotEnabled.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -24,25 +24,25 @@
 /**
  * @test
  * @summary Test that preview APIs throws exception when preview features not enabled
- * @run testng/othervm PreviewFeaturesNotEnabled
+ * @run junit/othervm PreviewFeaturesNotEnabled
  */
 
 import java.lang.reflect.Method;
 import java.lang.reflect.InvocationTargetException;
 import java.util.concurrent.Executors;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class PreviewFeaturesNotEnabled {
+class PreviewFeaturesNotEnabled {
 
     /**
      * Thread.ofVirtual should fail with UOE.
      */
     @Test
-    public void testOfVirtual() throws Exception {
+    void testOfVirtual() throws Exception {
         Method ofVirtual = Thread.class.getDeclaredMethod("ofVirtual");
-        var exc = expectThrows(InvocationTargetException.class, () -> ofVirtual.invoke(null));
+        var exc = assertThrows(InvocationTargetException.class, () -> ofVirtual.invoke(null));
         assertTrue(exc.getCause() instanceof UnsupportedOperationException);
     }
 
@@ -50,10 +50,10 @@ public class PreviewFeaturesNotEnabled {
      * Thread.startVirtualThread should fail with UOE.
      */
     @Test
-    public void testStartVirutalThread() throws Exception {
+    void testStartVirutalThread() throws Exception {
         Method startVirtualThread = Thread.class.getMethod("startVirtualThread", Runnable.class);
         Runnable task = () -> { };
-        var exc = expectThrows(InvocationTargetException.class,
+        var exc = assertThrows(InvocationTargetException.class,
                 () -> startVirtualThread.invoke(null, task));
         assertTrue(exc.getCause() instanceof UnsupportedOperationException);
     }
@@ -62,9 +62,9 @@ public class PreviewFeaturesNotEnabled {
      * Executors.newVirtualThreadPerTaskExecutor should fail with UOE.
      */
     @Test
-    public void testNewVirtualThreadPerTaskExecutor() throws Exception {
+    void testNewVirtualThreadPerTaskExecutor() throws Exception {
         Method newVirtualThreadPerTaskExecutor = Executors.class.getMethod("newVirtualThreadPerTaskExecutor");
-        var exc = expectThrows(InvocationTargetException.class,
+        var exc = assertThrows(InvocationTargetException.class,
                 () -> newVirtualThreadPerTaskExecutor.invoke(null));
         assertTrue(exc.getCause() instanceof UnsupportedOperationException);
     }
@@ -73,8 +73,8 @@ public class PreviewFeaturesNotEnabled {
      * Directly accessing internal Continuation class should fail with UOE.
      */
     @Test
-    public void testContinuationInitializer() throws Exception {
-        var exc = expectThrows(ExceptionInInitializerError.class,
+    void testContinuationInitializer() throws Exception {
+        var exc = assertThrows(ExceptionInInitializerError.class,
                 () -> Class.forName("jdk.internal.vm.Continuation"));
         assertTrue(exc.getCause() instanceof UnsupportedOperationException);
     }
@@ -83,7 +83,7 @@ public class PreviewFeaturesNotEnabled {
      * Thread.isVirtual should not fail.
      */
     @Test
-    public void testIsVirtual() throws Exception {
+    void testIsVirtual() throws Exception {
         boolean isVirtual = isVirtual(Thread.currentThread());
         assertFalse(isVirtual);
     }
@@ -92,7 +92,7 @@ public class PreviewFeaturesNotEnabled {
      * Thread.ofPlatform should not fail.
      */
     @Test
-    public void testOfPlatform() throws Exception {
+    void testOfPlatform() throws Exception {
         Method ofPlatform = Thread.class.getDeclaredMethod("ofPlatform");
         Object builder = ofPlatform.invoke(null);
         Method startMethod = Class.forName("java.lang.Thread$Builder")
diff --git a/test/jdk/java/lang/Thread/virtual/Reflection.java b/test/jdk/java/lang/Thread/virtual/Reflection.java
index 87b52072af6..23dcfb796b2 100644
--- a/test/jdk/java/lang/Thread/virtual/Reflection.java
+++ b/test/jdk/java/lang/Thread/virtual/Reflection.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
  * @modules java.base/java.lang:+open
  * @library /test/lib
  * @enablePreview
- * @run testng Reflection
+ * @run junit Reflection
  */
 
 import java.lang.reflect.Constructor;
@@ -39,17 +39,17 @@ import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.locks.LockSupport;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.SkipException;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assumptions.*;
 
-public class Reflection {
+class Reflection {
 
     /**
      * Test invoking static method.
      */
     @Test
-    public void testInvokeStatic1() throws Exception {
+    void testInvokeStatic1() throws Exception {
         VThreadRunner.run(() -> {
             int result = (int) divideMethod().invoke(null, 20, 2);
             assertTrue(result == 10);
@@ -61,7 +61,7 @@ public class Reflection {
      * exception.
      */
     @Test
-    public void testInvokeStatic2() throws Exception {
+    void testInvokeStatic2() throws Exception {
         VThreadRunner.run(() -> {
             try {
                 divideMethod().invoke(null, 20, 0);
@@ -77,7 +77,7 @@ public class Reflection {
      * method with bad parameters.
      */
     @Test
-    public void testInvokeStatic3() throws Exception {
+    void testInvokeStatic3() throws Exception {
         VThreadRunner.run(() -> {
             assertThrows(IllegalArgumentException.class,
                     () -> divideMethod().invoke(null));
@@ -99,7 +99,7 @@ public class Reflection {
      * method triggers its class to be initialized and it fails with exception.
      */
     @Test
-    public void testInvokeStatic4() throws Exception {
+    void testInvokeStatic4() throws Exception {
         VThreadRunner.run(() -> {
             Method foo = BadClass1.class.getDeclaredMethod("foo");
             try {
@@ -123,7 +123,7 @@ public class Reflection {
      * class to be initialized and it fails with an error.
      */
     @Test
-    public void testInvokeStatic5() throws Exception {
+    void testInvokeStatic5() throws Exception {
         VThreadRunner.run(() -> {
             Method foo = BadClass2.class.getDeclaredMethod("foo");
             assertThrows(AbstractMethodError.class, () -> foo.invoke(null));
@@ -141,9 +141,8 @@ public class Reflection {
      * Test that invoking a static method does not pin the carrier thread.
      */
     @Test
-    public void testInvokeStatic6() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testInvokeStatic6() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         Method parkMethod = Parker.class.getDeclaredMethod("park");
         try (ExecutorService scheduler = Executors.newFixedThreadPool(1)) {
             Thread.Builder builder = ThreadBuilders.virtualThreadBuilder(scheduler);
@@ -172,7 +171,7 @@ public class Reflection {
      * Test invoking instance method.
      */
     @Test
-    public void testInvokeInstance1() throws Exception {
+    void testInvokeInstance1() throws Exception {
         VThreadRunner.run(() -> {
             var adder = new Adder();
             Adder.addMethod().invoke(adder, 5);
@@ -185,7 +184,7 @@ public class Reflection {
      * exception.
      */
     @Test
-    public void testInvokeInstance2() throws Exception {
+    void testInvokeInstance2() throws Exception {
         VThreadRunner.run(() -> {
             var adder = new Adder();
             try {
@@ -202,7 +201,7 @@ public class Reflection {
      * trying to invoke an instance method with null or bad parameters.
      */
     @Test
-    public void testInvokeInstance3() throws Exception {
+    void testInvokeInstance3() throws Exception {
         VThreadRunner.run(() -> {
             var adder = new Adder();
             Method addMethod = Adder.addMethod();
@@ -223,7 +222,7 @@ public class Reflection {
      * Test invoking newInstance to create an object.
      */
     @Test
-    public void testNewInstance1() throws Exception {
+    void testNewInstance1() throws Exception {
         VThreadRunner.run(() -> {
             Constructor<?> ctor = Adder.class.getDeclaredConstructor(long.class);
             Adder adder = (Adder) ctor.newInstance(10);
@@ -236,7 +235,7 @@ public class Reflection {
      * exception.
      */
     @Test
-    public void testNewInstance2() throws Exception {
+    void testNewInstance2() throws Exception {
         VThreadRunner.run(() -> {
             Constructor<?> ctor = Adder.class.getDeclaredConstructor(long.class);
             try {
@@ -253,7 +252,7 @@ public class Reflection {
      * with bad parameters.
      */
     @Test
-    public void testNewInstance3() throws Exception {
+    void testNewInstance3() throws Exception {
         VThreadRunner.run(() -> {
             var adder = new Adder();
             Constructor<?> ctor = Adder.class.getDeclaredConstructor(long.class);
@@ -275,7 +274,7 @@ public class Reflection {
      * triggers the class to be initialized and it fails with exception.
      */
     @Test
-    public void testNewInstance4() throws Exception {
+    void testNewInstance4() throws Exception {
         VThreadRunner.run(() -> {
             Constructor<?> ctor = BadClass3.class.getDeclaredConstructor();
             try {
@@ -299,7 +298,7 @@ public class Reflection {
      * to be initialized and it fails with an error.
      */
     @Test
-    public void testNewInstance5() throws Exception {
+    void testNewInstance5() throws Exception {
         VThreadRunner.run(() -> {
             Constructor<?> ctor = BadClass4.class.getDeclaredConstructor();
             assertThrows(AbstractMethodError.class, () -> ctor.newInstance((Object[])null));
@@ -317,9 +316,8 @@ public class Reflection {
      * Test that newInstance does not pin the carrier thread
      */
     @Test
-    public void testNewInstance6() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testNewInstance6() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         Constructor<?> ctor = Parker.class.getDeclaredConstructor();
         try (ExecutorService scheduler = Executors.newFixedThreadPool(1)) {
             Thread.Builder builder = ThreadBuilders.virtualThreadBuilder(scheduler);
diff --git a/test/jdk/java/lang/Thread/virtual/StackTraces.java b/test/jdk/java/lang/Thread/virtual/StackTraces.java
index a269d424e59..824dfa0c3ef 100644
--- a/test/jdk/java/lang/Thread/virtual/StackTraces.java
+++ b/test/jdk/java/lang/Thread/virtual/StackTraces.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -29,8 +29,8 @@
  * @modules java.management
  * @library /test/lib
  * @enablePreview
- * @run testng StackTraces
- * @run testng/othervm -XX:+UnlockDiagnosticVMOptions -XX:+ShowCarrierFrames StackTraces
+ * @run junit StackTraces
+ * @run junit/othervm -XX:+UnlockDiagnosticVMOptions -XX:+ShowCarrierFrames StackTraces
  */
 
 import java.lang.management.ManagementFactory;
@@ -40,17 +40,17 @@ import java.util.concurrent.ForkJoinPool;
 import static java.lang.StackWalker.Option.*;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class StackTraces {
+class StackTraces {
 
     /**
      * Test that the stack trace in exceptions does not include the carrier thread
      * frames, except when running with -XX:+ShowCarrierFrames.
      */
     @Test
-    public void testStackTrace() throws Exception {
+    void testStackTrace() throws Exception {
         VThreadRunner.run(() -> {
             Exception e = new Exception();
             boolean found = Arrays.stream(e.getStackTrace())
@@ -64,7 +64,7 @@ public class StackTraces {
      * Test that StackWalker does not include carrier thread frames.
      */
     @Test
-    public void testStackWalker() throws Exception {
+    void testStackWalker() throws Exception {
         VThreadRunner.run(() -> {
             StackWalker walker = StackWalker.getInstance(Set.of(RETAIN_CLASS_REFERENCE));
             boolean found = walker.walk(sf ->
diff --git a/test/jdk/java/lang/Thread/virtual/ThreadAPI.java b/test/jdk/java/lang/Thread/virtual/ThreadAPI.java
index 9476694473f..97e67cfc57c 100644
--- a/test/jdk/java/lang/Thread/virtual/ThreadAPI.java
+++ b/test/jdk/java/lang/Thread/virtual/ThreadAPI.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,7 +28,7 @@
  * @enablePreview
  * @modules java.base/java.lang:+open
  * @library /test/lib
- * @run testng ThreadAPI
+ * @run junit ThreadAPI
  */
 
 /*
@@ -37,7 +37,7 @@
  * @enablePreview
  * @modules java.base/java.lang:+open
  * @library /test/lib
- * @run testng/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations ThreadAPI
+ * @run junit/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations ThreadAPI
  */
 
 import java.time.Duration;
@@ -63,31 +63,28 @@ import java.util.stream.Stream;
 import java.nio.channels.Selector;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.SkipException;
-import org.testng.annotations.AfterClass;
-import org.testng.annotations.BeforeClass;
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assumptions.*;
 
-public class ThreadAPI {
+class ThreadAPI {
     private static final Object lock = new Object();
 
     // used for scheduling thread interrupt
-    private ScheduledExecutorService scheduler;
+    private static ScheduledExecutorService scheduler;
 
-    @BeforeClass
-    public void setUp() throws Exception {
-        ThreadFactory factory = (task) -> {
-            Thread thread = new Thread(task);
-            thread.setDaemon(true);
-            return thread;
-        };
+    @BeforeAll
+    static void setup() throws Exception {
+        ThreadFactory factory = Executors.defaultThreadFactory();
         scheduler = Executors.newSingleThreadScheduledExecutor(factory);
     }
 
-    @AfterClass
-    public void tearDown() {
+    @AfterAll
+    static void finish() {
         scheduler.shutdown();
     }
 
@@ -103,7 +100,7 @@ public class ThreadAPI {
      * Test Thread.currentThread before/after park.
      */
     @Test
-    public void testCurrentThread1() throws Exception {
+    void testCurrentThread1() throws Exception {
         var before = new AtomicReference<Thread>();
         var after = new AtomicReference<Thread>();
         var thread = Thread.ofVirtual().start(() -> {
@@ -122,7 +119,7 @@ public class ThreadAPI {
      * Test Thread.currentThread before/after entering synchronized block.
      */
     @Test
-    public void testCurrentThread2() throws Exception {
+    void testCurrentThread2() throws Exception {
         var ref1 = new AtomicReference<Thread>();
         var ref2 = new AtomicReference<Thread>();
         var ref3 = new AtomicReference<Thread>();
@@ -147,7 +144,7 @@ public class ThreadAPI {
      * Test Thread.currentThread before/after acquiring lock.
      */
     @Test
-    public void testCurrentThread3() throws Exception {
+    void testCurrentThread3() throws Exception {
         var ref1 = new AtomicReference<Thread>();
         var ref2 = new AtomicReference<Thread>();
         var ref3 = new AtomicReference<Thread>();
@@ -179,7 +176,7 @@ public class ThreadAPI {
      * Test Thread::run.
      */
     @Test
-    public void testRun1() throws Exception {
+    void testRun1() throws Exception {
         var ref = new AtomicBoolean();
         var thread = Thread.ofVirtual().unstarted(() -> ref.set(true));
         thread.run();
@@ -190,7 +187,7 @@ public class ThreadAPI {
      * Test Thread::start.
      */
     @Test
-    public void testStart1() throws Exception {
+    void testStart1() throws Exception {
         var ref = new AtomicBoolean();
         var thread = Thread.ofVirtual().unstarted(() -> ref.set(true));
         assertFalse(ref.get());
@@ -203,7 +200,7 @@ public class ThreadAPI {
      * Test Thread::start, thread already started.
      */
     @Test
-    public void testStart2() throws Exception {
+    void testStart2() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         try {
             assertThrows(IllegalThreadStateException.class, thread::start);
@@ -217,7 +214,7 @@ public class ThreadAPI {
      * Test Thread::start, thread already terminated.
      */
     @Test
-    public void testStart3() throws Exception {
+    void testStart3() throws Exception {
         var thread = Thread.ofVirtual().start(() -> { });
         thread.join();
         assertThrows(IllegalThreadStateException.class, thread::start);
@@ -227,7 +224,7 @@ public class ThreadAPI {
      * Test Thread.startVirtualThread.
      */
     @Test
-    public void testStartVirtualThread() throws Exception {
+    void testStartVirtualThread() throws Exception {
         var ref = new AtomicReference<Thread>();
         Thread vthread = Thread.startVirtualThread(() -> {
             ref.set(Thread.currentThread());
@@ -253,7 +250,7 @@ public class ThreadAPI {
      * Test Thread::stop from current thread.
      */
     @Test
-    public void testStop1() throws Exception {
+    void testStop1() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             assertThrows(UnsupportedOperationException.class, t::stop);
@@ -264,7 +261,7 @@ public class ThreadAPI {
      * Test Thread::stop from another thread.
      */
     @Test
-    public void testStop2() throws Exception {
+    void testStop2() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             try {
                 Thread.sleep(20*1000);
@@ -282,7 +279,7 @@ public class ThreadAPI {
      * Test Thread::suspend from current thread.
      */
     @Test
-    public void testSuspend1() throws Exception {
+    void testSuspend1() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             assertThrows(UnsupportedOperationException.class, t::suspend);
@@ -293,7 +290,7 @@ public class ThreadAPI {
      * Test Thread::suspend from another thread.
      */
     @Test
-    public void testSuspend2() throws Exception {
+    void testSuspend2() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             try {
                 Thread.sleep(20*1000);
@@ -311,7 +308,7 @@ public class ThreadAPI {
      * Test Thread::resume from current thread.
      */
     @Test
-    public void testResume1() throws Exception {
+    void testResume1() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             assertThrows(UnsupportedOperationException.class, t::resume);
@@ -322,7 +319,7 @@ public class ThreadAPI {
      * Test Thread::resume from another thread.
      */
     @Test
-    public void testResume2() throws Exception {
+    void testResume2() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             try {
                 Thread.sleep(20*1000);
@@ -340,7 +337,7 @@ public class ThreadAPI {
      * Test Thread.join before thread starts, platform thread invokes join.
      */
     @Test
-    public void testJoin1() throws Exception {
+    void testJoin1() throws Exception {
         var thread = Thread.ofVirtual().unstarted(() -> { });
 
         thread.join();
@@ -360,7 +357,7 @@ public class ThreadAPI {
      * Test Thread.join before thread starts, virtual thread invokes join.
      */
     @Test
-    public void testJoin2() throws Exception {
+    void testJoin2() throws Exception {
         VThreadRunner.run(this::testJoin1);
     }
 
@@ -368,7 +365,7 @@ public class ThreadAPI {
      * Test Thread.join where thread does not terminate, platform thread invokes join.
      */
     @Test
-    public void testJoin3() throws Exception {
+    void testJoin3() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         try {
             thread.join(20);
@@ -389,7 +386,7 @@ public class ThreadAPI {
      * Test Thread.join where thread does not terminate, virtual thread invokes join.
      */
     @Test
-    public void testJoin4() throws Exception {
+    void testJoin4() throws Exception {
         VThreadRunner.run(this::testJoin3);
     }
 
@@ -397,7 +394,7 @@ public class ThreadAPI {
      * Test Thread.join where thread terminates, platform thread invokes join.
      */
     @Test
-    public void testJoin5() throws Exception {
+    void testJoin5() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             try {
                 Thread.sleep(50);
@@ -411,7 +408,7 @@ public class ThreadAPI {
      * Test Thread.join where thread terminates, virtual thread invokes join.
      */
     @Test
-    public void testJoin6() throws Exception {
+    void testJoin6() throws Exception {
         VThreadRunner.run(this::testJoin5);
     }
 
@@ -419,7 +416,7 @@ public class ThreadAPI {
      * Test Thread.join where thread terminates, platform thread invokes timed-join.
      */
     @Test
-    public void testJoin7() throws Exception {
+    void testJoin7() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             try {
                 Thread.sleep(50);
@@ -433,7 +430,7 @@ public class ThreadAPI {
      * Test Thread.join where thread terminates, virtual thread invokes timed-join.
      */
     @Test
-    public void testJoin8() throws Exception {
+    void testJoin8() throws Exception {
         VThreadRunner.run(this::testJoin7);
     }
 
@@ -441,7 +438,7 @@ public class ThreadAPI {
      * Test Thread.join where thread terminates, platform thread invokes timed-join.
      */
     @Test
-    public void testJoin11() throws Exception {
+    void testJoin11() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             try {
                 Thread.sleep(50);
@@ -455,7 +452,7 @@ public class ThreadAPI {
      * Test Thread.join where thread terminates, virtual thread invokes timed-join.
      */
     @Test
-    public void testJoin12() throws Exception {
+    void testJoin12() throws Exception {
         VThreadRunner.run(this::testJoin11);
     }
 
@@ -463,7 +460,7 @@ public class ThreadAPI {
      * Test Thread.join where thread already terminated, platform thread invokes join.
      */
     @Test
-    public void testJoin13() throws Exception {
+    void testJoin13() throws Exception {
         var thread = Thread.ofVirtual().start(() -> { });
         while (thread.isAlive()) {
             Thread.sleep(10);
@@ -482,7 +479,7 @@ public class ThreadAPI {
      * Test Thread.join where thread already terminated, virtual thread invokes join.
      */
     @Test
-    public void testJoin14() throws Exception {
+    void testJoin14() throws Exception {
         VThreadRunner.run(this::testJoin13);
     }
 
@@ -490,7 +487,7 @@ public class ThreadAPI {
      * Test platform thread invoking Thread.join with interrupt status set.
      */
     @Test
-    public void testJoin15() throws Exception {
+    void testJoin15() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         Thread.currentThread().interrupt();
         try {
@@ -506,7 +503,7 @@ public class ThreadAPI {
      * Test virtual thread invoking Thread.join with interrupt status set.
      */
     @Test
-    public void testJoin16() throws Exception {
+    void testJoin16() throws Exception {
         VThreadRunner.run(this::testJoin15);
     }
 
@@ -514,7 +511,7 @@ public class ThreadAPI {
      * Test platform thread invoking timed-Thread.join with interrupt status set.
      */
     @Test
-    public void testJoin17() throws Exception {
+    void testJoin17() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         Thread.currentThread().interrupt();
         try {
@@ -530,7 +527,7 @@ public class ThreadAPI {
      * Test virtual thread invoking timed-Thread.join with interrupt status set.
      */
     @Test
-    public void testJoin18() throws Exception {
+    void testJoin18() throws Exception {
         VThreadRunner.run(this::testJoin17);
     }
 
@@ -538,7 +535,7 @@ public class ThreadAPI {
      * Test platform thread invoking timed-Thread.join with interrupt status set.
      */
     @Test
-    public void testJoin19() throws Exception {
+    void testJoin19() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         Thread.currentThread().interrupt();
         try {
@@ -555,7 +552,7 @@ public class ThreadAPI {
      * Test virtual thread invoking timed-Thread.join with interrupt status set.
      */
     @Test
-    public void testJoin20() throws Exception {
+    void testJoin20() throws Exception {
         VThreadRunner.run(this::testJoin19);
     }
 
@@ -563,7 +560,7 @@ public class ThreadAPI {
      * Test interrupt of platform thread blocked in Thread.join.
      */
     @Test
-    public void testJoin21() throws Exception {
+    void testJoin21() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         scheduleInterrupt(Thread.currentThread(), 100);
         try {
@@ -579,7 +576,7 @@ public class ThreadAPI {
      * Test interrupt of virtual thread blocked in Thread.join.
      */
     @Test
-    public void testJoin22() throws Exception {
+    void testJoin22() throws Exception {
         VThreadRunner.run(this::testJoin17);
     }
 
@@ -587,7 +584,7 @@ public class ThreadAPI {
      * Test interrupt of platform thread blocked in timed-Thread.join.
      */
     @Test
-    public void testJoin23() throws Exception {
+    void testJoin23() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         scheduleInterrupt(Thread.currentThread(), 100);
         try {
@@ -603,7 +600,7 @@ public class ThreadAPI {
      * Test interrupt of virtual thread blocked in Thread.join.
      */
     @Test
-    public void testJoin24() throws Exception {
+    void testJoin24() throws Exception {
         VThreadRunner.run(this::testJoin23);
     }
 
@@ -611,7 +608,7 @@ public class ThreadAPI {
      * Test interrupt of platform thread blocked in Thread.join.
      */
     @Test
-    public void testJoin25() throws Exception {
+    void testJoin25() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         scheduleInterrupt(Thread.currentThread(), 100);
         try {
@@ -628,7 +625,7 @@ public class ThreadAPI {
      * Test interrupt of virtual thread blocked in Thread.join.
      */
     @Test
-    public void testJoin26() throws Exception {
+    void testJoin26() throws Exception {
         VThreadRunner.run(this::testJoin25);
     }
 
@@ -636,7 +633,7 @@ public class ThreadAPI {
      * Test virtual thread calling Thread.join to wait for platform thread to terminate.
      */
     @Test
-    public void testJoin27() throws Exception {
+    void testJoin27() throws Exception {
         AtomicBoolean done = new AtomicBoolean();
         VThreadRunner.run(() -> {
             var thread = new Thread(() -> {
@@ -661,7 +658,7 @@ public class ThreadAPI {
      * Test virtual thread calling Thread.join to wait for platform thread to terminate.
      */
     @Test
-    public void testJoin28() throws Exception {
+    void testJoin28() throws Exception {
         long nanos = TimeUnit.NANOSECONDS.convert(100, TimeUnit.MILLISECONDS);
         VThreadRunner.run(() -> {
             var thread = new Thread(() -> LockSupport.parkNanos(nanos));
@@ -681,7 +678,7 @@ public class ThreadAPI {
      * for platform thread to terminate.
      */
     @Test
-    public void testJoin29() throws Exception {
+    void testJoin29() throws Exception {
         VThreadRunner.run(() -> {
             var thread = new Thread(LockSupport::park);
             thread.start();
@@ -703,7 +700,7 @@ public class ThreadAPI {
      * platform thread to terminate.
      */
     @Test
-    public void testJoin30() throws Exception {
+    void testJoin30() throws Exception {
         VThreadRunner.run(() -> {
             AtomicBoolean done = new AtomicBoolean();
             var thread = new Thread(() -> {
@@ -731,7 +728,7 @@ public class ThreadAPI {
      * and unparking.
      */
     @Test
-    public void testJoin31() throws Exception {
+    void testJoin31() throws Exception {
         Thread thread = Thread.ofVirtual().start(() -> {
             synchronized (lock) {
                 for (int i = 0; i < 10; i++) {
@@ -748,7 +745,7 @@ public class ThreadAPI {
      * and unparking.
      */
     @Test
-    public void testJoin32() throws Exception {
+    void testJoin32() throws Exception {
         VThreadRunner.run(this::testJoin31);
     }
 
@@ -757,7 +754,7 @@ public class ThreadAPI {
      * and unparking while pinned.
      */
     @Test
-    public void testJoin33() throws Exception {
+    void testJoin33() throws Exception {
         AtomicBoolean done = new AtomicBoolean();
         Thread thread = Thread.ofVirtual().start(() -> {
             synchronized (lock) {
@@ -778,7 +775,7 @@ public class ThreadAPI {
      * and unparking while pinned.
      */
     @Test
-    public void testJoin34() throws Exception {
+    void testJoin34() throws Exception {
         // need at least two carrier threads due to pinning
         int previousParallelism = VThreadRunner.ensureParallelism(2);
         try {
@@ -793,7 +790,7 @@ public class ThreadAPI {
      * Test Thread.join(null).
      */
     @Test
-    public void testJoin35() throws Exception {
+    void testJoin35() throws Exception {
         var thread = Thread.ofVirtual().unstarted(LockSupport::park);
 
         // unstarted
@@ -816,7 +813,7 @@ public class ThreadAPI {
      * Test Thread.interrupt on current thread.
      */
     @Test
-    public void testInterrupt1() throws Exception {
+    void testInterrupt1() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             assertFalse(me.isInterrupted());
@@ -832,7 +829,7 @@ public class ThreadAPI {
      * Test Thread.interrupt before thread started.
      */
     @Test
-    public void testInterrupt2() throws Exception {
+    void testInterrupt2() throws Exception {
         var thread = Thread.ofVirtual().unstarted(() -> { });
         thread.interrupt();
         assertTrue(thread.isInterrupted());
@@ -842,7 +839,7 @@ public class ThreadAPI {
      * Test Thread.interrupt after thread started.
      */
     @Test
-    public void testInterrupt3() throws Exception {
+    void testInterrupt3() throws Exception {
         var thread = Thread.ofVirtual().start(() -> { });
         thread.join();
         thread.interrupt();
@@ -853,7 +850,7 @@ public class ThreadAPI {
      * Test termination with interrupt status set.
      */
     @Test
-    public void testInterrupt4() throws Exception {
+    void testInterrupt4() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             Thread.currentThread().interrupt();
         });
@@ -865,7 +862,7 @@ public class ThreadAPI {
      * Test Thread.interrupt of thread blocked in Selector.select.
      */
     @Test
-    public void testInterrupt5() throws Exception {
+    void testInterrupt5() throws Exception {
         var exception = new AtomicReference<Exception>();
         var thread = Thread.ofVirtual().start(() -> {
             try {
@@ -880,14 +877,14 @@ public class ThreadAPI {
         Thread.sleep(100);  // give time for thread to block
         thread.interrupt();
         thread.join();
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test Thread.interrupt of thread parked in sleep.
      */
     @Test
-    public void testInterrupt6() throws Exception {
+    void testInterrupt6() throws Exception {
         var exception = new AtomicReference<Exception>();
         var thread = Thread.ofVirtual().start(() -> {
             try {
@@ -905,14 +902,14 @@ public class ThreadAPI {
         awaitParked(thread);
         thread.interrupt();
         thread.join();
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test Thread.interrupt of parked thread.
      */
     @Test
-    public void testInterrupt7() throws Exception {
+    void testInterrupt7() throws Exception {
         var exception = new AtomicReference<Exception>();
         var thread = Thread.ofVirtual().start(() -> {
             try {
@@ -925,14 +922,14 @@ public class ThreadAPI {
         awaitParked(thread);
         thread.interrupt();
         thread.join();
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test trying to park with interrupt status set.
      */
     @Test
-    public void testInterrupt8() throws Exception {
+    void testInterrupt8() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             me.interrupt();
@@ -945,7 +942,7 @@ public class ThreadAPI {
      * Test trying to wait with interrupt status set.
      */
     @Test
-    public void testInterrupt9() throws Exception {
+    void testInterrupt9() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             me.interrupt();
@@ -964,7 +961,7 @@ public class ThreadAPI {
      * Test trying to block with interrupt status set.
      */
     @Test
-    public void testInterrupt10() throws Exception {
+    void testInterrupt10() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             me.interrupt();
@@ -979,12 +976,12 @@ public class ThreadAPI {
      * Test Thread.getName and setName from current thread, started without name.
      */
     @Test
-    public void testSetName1() throws Exception {
+    void testSetName1() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             assertTrue(me.getName().isEmpty());
             me.setName("fred");
-            assertEquals(me.getName(), "fred");
+            assertEquals("fred", me.getName());
         });
     }
 
@@ -992,12 +989,12 @@ public class ThreadAPI {
      * Test Thread.getName and setName from current thread, started with name.
      */
     @Test
-    public void testSetName2() throws Exception {
+    void testSetName2() throws Exception {
         VThreadRunner.run("fred", () -> {
             Thread me = Thread.currentThread();
-            assertEquals(me.getName(), "fred");
+            assertEquals("fred", me.getName());
             me.setName("joe");
-            assertEquals(me.getName(), "joe");
+            assertEquals("joe", me.getName());
         });
     }
 
@@ -1005,36 +1002,36 @@ public class ThreadAPI {
      * Test Thread.getName and setName from another thread.
      */
     @Test
-    public void testSetName3() throws Exception {
+    void testSetName3() throws Exception {
         var thread = Thread.ofVirtual().unstarted(LockSupport::park);
         assertTrue(thread.getName().isEmpty());
 
         // not started
         thread.setName("fred1");
-        assertEquals(thread.getName(), "fred1");
+        assertEquals("fred1", thread.getName());
 
         // started
         thread.start();
         try {
-            assertEquals(thread.getName(), "fred1");
+            assertEquals("fred1", thread.getName());
             thread.setName("fred2");
-            assertEquals(thread.getName(), "fred2");
+            assertEquals("fred2", thread.getName());
         } finally {
             LockSupport.unpark(thread);
             thread.join();
         }
 
         // terminated
-        assertEquals(thread.getName(), "fred2");
+        assertEquals("fred2", thread.getName());
         thread.setName("fred3");
-        assertEquals(thread.getName(), "fred3");
+        assertEquals("fred3", thread.getName());
     }
 
     /**
      * Test Thread.getPriority and setPriority from current thread.
      */
     @Test
-    public void testSetPriority1() throws Exception {
+    void testSetPriority1() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             assertTrue(me.getPriority() == Thread.NORM_PRIORITY);
@@ -1056,7 +1053,7 @@ public class ThreadAPI {
      * Test Thread.getPriority and setPriority from another thread.
      */
     @Test
-    public void testSetPriority2() throws Exception {
+    void testSetPriority2() throws Exception {
         var thread = Thread.ofVirtual().unstarted(LockSupport::park);
 
         // not started
@@ -1103,7 +1100,7 @@ public class ThreadAPI {
      * Test Thread.isDaemon and setDaemon from current thread.
      */
     @Test
-    public void testSetDaemon1() throws Exception {
+    void testSetDaemon1() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             assertTrue(me.isDaemon());
@@ -1116,7 +1113,7 @@ public class ThreadAPI {
      * Test Thread.isDaemon and setDaemon from another thread.
      */
     @Test
-    public void testSetDaemon2() throws Exception {
+    void testSetDaemon2() throws Exception {
         var thread = Thread.ofVirtual().unstarted(LockSupport::park);
 
         // not started
@@ -1143,9 +1140,8 @@ public class ThreadAPI {
      * Test Thread.yield releases thread when not pinned.
      */
     @Test
-    public void testYield1() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testYield1() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         var list = new CopyOnWriteArrayList<String>();
         try (ExecutorService scheduler = Executors.newFixedThreadPool(1)) {
             Thread.Builder builder = ThreadBuilders.virtualThreadBuilder(scheduler);
@@ -1165,16 +1161,15 @@ public class ThreadAPI {
             thread.start();
             thread.join();
         }
-        assertEquals(list, List.of("A", "B", "A", "B"));
+        assertEquals(List.of("A", "B", "A", "B"), list);
     }
 
     /**
      * Test Thread.yield when thread is pinned.
      */
     @Test
-    public void testYield2() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testYield2() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         var list = new CopyOnWriteArrayList<String>();
         try (ExecutorService scheduler = Executors.newFixedThreadPool(1)) {
             Thread.Builder builder = ThreadBuilders.virtualThreadBuilder(scheduler);
@@ -1194,14 +1189,14 @@ public class ThreadAPI {
             thread.start();
             thread.join();
         }
-        assertEquals(list, List.of("A", "A", "B"));
+        assertEquals(List.of("A", "A", "B"), list);
     }
 
     /**
      * Test Thread.onSpinWait.
      */
     @Test
-    public void testOnSpinWait() throws Exception {
+    void testOnSpinWait() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             Thread.onSpinWait();
@@ -1213,7 +1208,7 @@ public class ThreadAPI {
      * Test Thread.sleep(-1).
      */
     @Test
-    public void testSleep1() throws Exception {
+    void testSleep1() throws Exception {
         VThreadRunner.run(() -> {
             assertThrows(IllegalArgumentException.class, () -> Thread.sleep(-1));
             assertThrows(IllegalArgumentException.class, () -> Thread.sleep(-1, 0));
@@ -1227,7 +1222,7 @@ public class ThreadAPI {
      * Test Thread.sleep(0).
      */
     @Test
-    public void testSleep2() throws Exception {
+    void testSleep2() throws Exception {
         VThreadRunner.run(() -> Thread.sleep(0));
         VThreadRunner.run(() -> Thread.sleep(0, 0));
         VThreadRunner.run(() -> Thread.sleep(Duration.ofMillis(0)));
@@ -1236,22 +1231,19 @@ public class ThreadAPI {
     /**
      * Tasks that sleep for 1 second.
      */
-    @DataProvider(name = "oneSecondSleepers")
-    public Object[][] oneSecondSleepers() {
-        ThrowingRunnable[] sleepers = {
+    static Stream<ThrowingRunnable> oneSecondSleepers() {
+        return Stream.of(
                 () -> Thread.sleep(1000),
                 () -> Thread.sleep(Duration.ofSeconds(1))
-        };
-        return Arrays.stream(sleepers)
-                .map(s -> new Object[] { s })
-                .toArray(Object[][]::new);
+        );
     }
 
     /**
      * Test Thread.sleep duration.
      */
-    @Test(dataProvider = "oneSecondSleepers")
-    public void testSleep3(ThrowingRunnable sleeper) throws Exception {
+    @ParameterizedTest
+    @MethodSource("oneSecondSleepers")
+    void testSleep3(ThrowingRunnable sleeper) throws Exception {
         VThreadRunner.run(() -> {
             long start = millisTime();
             sleeper.run();
@@ -1262,26 +1254,23 @@ public class ThreadAPI {
     /**
      * Tasks that sleep for zero or longer duration.
      */
-    @DataProvider(name = "sleepers")
-    public Object[][] sleepers() {
-        ThrowingRunnable[] sleepers = {
+    static Stream<ThrowingRunnable> sleepers() {
+        return Stream.of(
                 () -> Thread.sleep(0),
                 () -> Thread.sleep(0, 0),
                 () -> Thread.sleep(1000),
                 () -> Thread.sleep(1000, 0),
                 () -> Thread.sleep(Duration.ofMillis(0)),
-                () -> Thread.sleep(Duration.ofMillis(1000)),
-        };
-        return Arrays.stream(sleepers)
-                .map(s -> new Object[] { s })
-                .toArray(Object[][]::new);
+                () -> Thread.sleep(Duration.ofMillis(1000))
+        );
     }
 
     /**
      * Test Thread.sleep with interrupt status set.
      */
-    @Test(dataProvider = "sleepers")
-    public void testSleep4(ThrowingRunnable sleeper) throws Exception {
+    @ParameterizedTest
+    @MethodSource("sleepers")
+    void testSleep4(ThrowingRunnable sleeper) throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             me.interrupt();
@@ -1299,7 +1288,7 @@ public class ThreadAPI {
      * Test Thread.sleep with interrupt status set and a negative duration.
      */
     @Test
-    public void testSleep4() throws Exception {
+    void testSleep4() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             me.interrupt();
@@ -1311,23 +1300,20 @@ public class ThreadAPI {
     /**
      * Tasks that sleep for a long time.
      */
-    @DataProvider(name = "longSleepers")
-    public Object[][] longSleepers() {
-        ThrowingRunnable[] sleepers = {
+    static Stream<ThrowingRunnable> longSleepers() {
+        return Stream.of(
                 () -> Thread.sleep(20_000),
                 () -> Thread.sleep(20_000, 0),
-                () -> Thread.sleep(Duration.ofSeconds(20)),
-        };
-        return Arrays.stream(sleepers)
-                .map(s -> new Object[] { s })
-                .toArray(Object[][]::new);
+                () -> Thread.sleep(Duration.ofSeconds(20))
+        );
     }
 
     /**
      * Test interrupting Thread.sleep.
      */
-    @Test(dataProvider = "longSleepers")
-    public void testSleep5(ThrowingRunnable sleeper) throws Exception {
+    @ParameterizedTest
+    @MethodSource("longSleepers")
+    void testSleep5(ThrowingRunnable sleeper) throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             scheduleInterrupt(t, 100);
@@ -1345,7 +1331,7 @@ public class ThreadAPI {
      * Test that Thread.sleep does not disrupt parking permit.
      */
     @Test
-    public void testSleep6() throws Exception {
+    void testSleep6() throws Exception {
         VThreadRunner.run(() -> {
             LockSupport.unpark(Thread.currentThread());
 
@@ -1362,7 +1348,7 @@ public class ThreadAPI {
      * Test that Thread.sleep is not disrupted by unparking thread.
      */
     @Test
-    public void testSleep7() throws Exception {
+    void testSleep7() throws Exception {
         AtomicReference<Exception> exc = new AtomicReference<>();
         var thread = Thread.ofVirtual().start(() -> {
             try {
@@ -1390,7 +1376,7 @@ public class ThreadAPI {
      * Test Thread.sleep when pinned.
      */
     @Test
-    public void testSleep8() throws Exception {
+    void testSleep8() throws Exception {
         VThreadRunner.run(() -> {
             long start = millisTime();
             synchronized (lock) {
@@ -1404,7 +1390,7 @@ public class ThreadAPI {
      * Test Thread.sleep when pinned and with interrupt status set.
      */
     @Test
-    public void testSleep9() throws Exception {
+    void testSleep9() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             me.interrupt();
@@ -1424,7 +1410,7 @@ public class ThreadAPI {
      * Test interrupting Thread.sleep when pinned.
      */
     @Test
-    public void testSleep10() throws Exception {
+    void testSleep10() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             scheduleInterrupt(t, 100);
@@ -1444,7 +1430,7 @@ public class ThreadAPI {
      * Test Thread.sleep(null).
      */
     @Test
-    public void testSleep11() throws Exception {
+    void testSleep11() throws Exception {
         assertThrows(NullPointerException.class, () -> Thread.sleep(null));
         VThreadRunner.run(() -> {
             assertThrows(NullPointerException.class, () -> Thread.sleep(null));
@@ -1478,7 +1464,7 @@ public class ThreadAPI {
      * Test Thread.xxxContextClassLoader from the current thread.
      */
     @Test
-    public void testContextClassLoader1() throws Exception {
+    void testContextClassLoader1() throws Exception {
         ClassLoader loader = new ClassLoader() { };
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
@@ -1491,7 +1477,7 @@ public class ThreadAPI {
      * Test inheriting initial value of TCCL from platform thread.
      */
     @Test
-    public void testContextClassLoader2() throws Exception {
+    void testContextClassLoader2() throws Exception {
         ClassLoader loader = new ClassLoader() { };
         Thread t = Thread.currentThread();
         ClassLoader savedLoader = t.getContextClassLoader();
@@ -1509,7 +1495,7 @@ public class ThreadAPI {
      * Test inheriting initial value of TCCL from virtual thread.
      */
     @Test
-    public void testContextClassLoader3() throws Exception {
+    void testContextClassLoader3() throws Exception {
         VThreadRunner.run(() -> {
             ClassLoader loader = new ClassLoader() { };
             Thread.currentThread().setContextClassLoader(loader);
@@ -1523,7 +1509,7 @@ public class ThreadAPI {
      * Test inheriting initial value of TCCL through an intermediate virtual thread.
      */
     @Test
-    public void testContextClassLoader4() throws Exception {
+    void testContextClassLoader4() throws Exception {
         ClassLoader loader = new ClassLoader() { };
         Thread t = Thread.currentThread();
         ClassLoader savedLoader = t.getContextClassLoader();
@@ -1543,7 +1529,7 @@ public class ThreadAPI {
      * Test Thread.xxxContextClassLoader when thread locals not supported.
      */
     @Test
-    public void testContextClassLoader5() throws Exception {
+    void testContextClassLoader5() throws Exception {
         ClassLoader scl = ClassLoader.getSystemClassLoader();
         ClassLoader loader = new ClassLoader() { };
         VThreadRunner.run(VThreadRunner.NO_THREAD_LOCALS, () -> {
@@ -1560,7 +1546,7 @@ public class ThreadAPI {
      * initial value of inheritable thread locals.
      */
     @Test
-    public void testContextClassLoader6() throws Exception {
+    void testContextClassLoader6() throws Exception {
         VThreadRunner.run(() -> {
             ClassLoader loader = new ClassLoader() { };
             Thread.currentThread().setContextClassLoader(loader);
@@ -1578,7 +1564,7 @@ public class ThreadAPI {
      * Test Thread.setUncaughtExceptionHandler.
      */
     @Test
-    public void testUncaughtExceptionHandler1() throws Exception {
+    void testUncaughtExceptionHandler1() throws Exception {
         class FooException extends RuntimeException { }
         var exception = new AtomicReference<Throwable>();
         Thread.UncaughtExceptionHandler handler = (thread, exc) -> exception.set(exc);
@@ -1591,14 +1577,14 @@ public class ThreadAPI {
         });
         thread.join();
         assertTrue(exception.get() instanceof FooException);
-        assertTrue(thread.getUncaughtExceptionHandler() == null);
+        assertNull(thread.getUncaughtExceptionHandler());
     }
 
     /**
      * Test default UncaughtExceptionHandler.
      */
     @Test
-    public void testUncaughtExceptionHandler2() throws Exception {
+    void testUncaughtExceptionHandler2() throws Exception {
         class FooException extends RuntimeException { }
         var exception = new AtomicReference<Throwable>();
         Thread.UncaughtExceptionHandler handler = (thread, exc) -> exception.set(exc);
@@ -1615,27 +1601,27 @@ public class ThreadAPI {
             Thread.setDefaultUncaughtExceptionHandler(savedHandler);
         }
         assertTrue(exception.get() instanceof FooException);
-        assertTrue(thread.getUncaughtExceptionHandler() == null);
+        assertNull(thread.getUncaughtExceptionHandler());
     }
 
     /**
      * Test no UncaughtExceptionHandler set.
      */
     @Test
-    public void testUncaughtExceptionHandler3() throws Exception {
+    void testUncaughtExceptionHandler3() throws Exception {
         class FooException extends RuntimeException { }
         Thread thread = Thread.ofVirtual().start(() -> {
             throw new FooException();
         });
         thread.join();
-        assertTrue(thread.getUncaughtExceptionHandler() == null);
+        assertNull(thread.getUncaughtExceptionHandler());
     }
 
     /**
      * Test Thread::threadId and getId.
      */
     @Test
-    public void testThreadId1() throws Exception {
+    void testThreadId1() throws Exception {
         record ThreadIds(long threadId, long id) { }
         var ref = new AtomicReference<ThreadIds>();
 
@@ -1671,7 +1657,7 @@ public class ThreadAPI {
      * Test that each Thread has a unique ID
      */
     @Test
-    public void testThreadId2() throws Exception {
+    void testThreadId2() throws Exception {
         // thread ID should be unique
         long tid1 = Thread.ofVirtual().unstarted(() -> { }).threadId();
         long tid2 = Thread.ofVirtual().unstarted(() -> { }).threadId();
@@ -1685,7 +1671,7 @@ public class ThreadAPI {
      * Test Thread::getState when thread is not started.
      */
     @Test
-    public void testGetState1() {
+    void testGetState1() {
         var thread = Thread.ofVirtual().unstarted(() -> { });
         assertTrue(thread.getState() == Thread.State.NEW);
     }
@@ -1694,7 +1680,7 @@ public class ThreadAPI {
      * Test Thread::getState when thread is runnable (mounted).
      */
     @Test
-    public void testGetState2() throws Exception {
+    void testGetState2() throws Exception {
         VThreadRunner.run(() -> {
             Thread.State state = Thread.currentThread().getState();
             assertTrue(state == Thread.State.RUNNABLE);
@@ -1705,9 +1691,8 @@ public class ThreadAPI {
      * Test Thread::getState when thread is runnable (not mounted).
      */
     @Test
-    public void testGetState3() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testGetState3() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         AtomicBoolean completed = new AtomicBoolean();
         try (ExecutorService scheduler = Executors.newFixedThreadPool(1)) {
             Thread.Builder builder = ThreadBuilders.virtualThreadBuilder(scheduler);
@@ -1742,7 +1727,7 @@ public class ThreadAPI {
      * Test Thread::getState when thread is parked.
      */
     @Test
-    public void testGetState4() throws Exception {
+    void testGetState4() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
         while (thread.getState() != Thread.State.WAITING) {
             Thread.sleep(20);
@@ -1755,7 +1740,7 @@ public class ThreadAPI {
      * Test Thread::getState when thread is parked while holding a monitor.
      */
     @Test
-    public void testGetState5() throws Exception {
+    void testGetState5() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             synchronized (lock) {
                 LockSupport.park();
@@ -1772,7 +1757,7 @@ public class ThreadAPI {
      * Test Thread::getState when thread is waiting for a monitor.
      */
     @Test
-    public void testGetState6() throws Exception {
+    void testGetState6() throws Exception {
         var thread = Thread.ofVirtual().unstarted(() -> {
             synchronized (lock) { }
         });
@@ -1789,7 +1774,7 @@ public class ThreadAPI {
      * Test Thread::getState when thread is waiting in Object.wait.
      */
     @Test
-    public void testGetState7() throws Exception {
+    void testGetState7() throws Exception {
         var thread = Thread.ofVirtual().start(() -> {
             synchronized (lock) {
                 try { lock.wait(); } catch (InterruptedException e) { }
@@ -1806,7 +1791,7 @@ public class ThreadAPI {
      * Test Thread::getState when thread is terminated.
      */
     @Test
-    public void testGetState8() throws Exception {
+    void testGetState8() throws Exception {
         var thread = Thread.ofVirtual().start(() -> { });
         thread.join();
         assertTrue(thread.getState() == Thread.State.TERMINATED);
@@ -1816,7 +1801,7 @@ public class ThreadAPI {
      * Test Thread::isAlive.
      */
     @Test
-    public void testIsAlive1() throws Exception {
+    void testIsAlive1() throws Exception {
         // unstarted
         var thread = Thread.ofVirtual().unstarted(LockSupport::park);
         assertFalse(thread.isAlive());
@@ -1838,7 +1823,7 @@ public class ThreadAPI {
      * Test Thread.holdLock when lock not held.
      */
     @Test
-    public void testHoldsLock1() throws Exception {
+    void testHoldsLock1() throws Exception {
         VThreadRunner.run(() -> {
             var lock = new Object();
             assertFalse(Thread.holdsLock(lock));
@@ -1849,7 +1834,7 @@ public class ThreadAPI {
      * Test Thread.holdLock when lock held.
      */
     @Test
-    public void testHoldsLock2() throws Exception {
+    void testHoldsLock2() throws Exception {
         VThreadRunner.run(() -> {
             var lock = new Object();
             synchronized (lock) {
@@ -1862,7 +1847,7 @@ public class ThreadAPI {
      * Test Thread::getStackTrace on unstarted thread.
      */
     @Test
-    public void testGetStackTrace1() {
+    void testGetStackTrace1() {
         var thread = Thread.ofVirtual().unstarted(() -> { });
         StackTraceElement[] stack = thread.getStackTrace();
         assertTrue(stack.length == 0);
@@ -1872,9 +1857,8 @@ public class ThreadAPI {
      * Test Thread::getStackTrace on thread that has been started but has not run.
      */
     @Test
-    public void testGetStackTrace2() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("Requires continuations support");
+    void testGetStackTrace2() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         Executor scheduler = task -> { };
         Thread.Builder builder = ThreadBuilders.virtualThreadBuilder(scheduler);
         Thread thread = builder.start(() -> { });
@@ -1886,7 +1870,7 @@ public class ThreadAPI {
      * Test Thread::getStackTrace on running thread.
      */
     @Test
-    public void testGetStackTrace3() throws Exception {
+    void testGetStackTrace3() throws Exception {
         var sel = Selector.open();
         var thread = Thread.ofVirtual().start(() -> {
             try { sel.select(); } catch (Exception e) { }
@@ -1906,9 +1890,8 @@ public class ThreadAPI {
      * Test Thread::getStackTrace on thread waiting in Object.wait.
      */
     @Test
-    public void testGetStackTrace4() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testGetStackTrace4() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         try (ForkJoinPool pool = new ForkJoinPool(1)) {
             AtomicReference<Thread> ref = new AtomicReference<>();
             Executor scheduler = task -> {
@@ -1961,7 +1944,7 @@ public class ThreadAPI {
      * Test Thread::getStackTrace on parked thread.
      */
     @Test
-    public void testGetStackTrace5() throws Exception {
+    void testGetStackTrace5() throws Exception {
         var thread = Thread.ofVirtual().start(LockSupport::park);
 
         // wait for thread to park
@@ -1982,7 +1965,7 @@ public class ThreadAPI {
      * Test Thread::getStackTrace on terminated thread.
      */
     @Test
-    public void testGetStackTrace6() throws Exception {
+    void testGetStackTrace6() throws Exception {
         var thread = Thread.ofVirtual().start(() -> { });
         thread.join();
         StackTraceElement[] stack = thread.getStackTrace();
@@ -1993,7 +1976,7 @@ public class ThreadAPI {
      * Test that Thread.getAllStackTraces does not include virtual threads.
      */
     @Test
-    public void testGetAllStackTraces1() throws Exception {
+    void testGetAllStackTraces1() throws Exception {
         VThreadRunner.run(() -> {
             Set<Thread> threads = Thread.getAllStackTraces().keySet();
             assertFalse(threads.stream().anyMatch(Thread::isVirtual));
@@ -2004,9 +1987,8 @@ public class ThreadAPI {
      * Test that Thread.getAllStackTraces includes carrier threads.
      */
     @Test
-    public void testGetAllStackTraces2() throws Exception {
-        if (!ThreadBuilders.supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testGetAllStackTraces2() throws Exception {
+        assumeTrue(ThreadBuilders.supportsCustomScheduler(), "No support for custom schedulers");
         try (ForkJoinPool pool = new ForkJoinPool(1)) {
             AtomicReference<Thread> ref = new AtomicReference<>();
             Executor scheduler = task -> {
@@ -2046,12 +2028,12 @@ public class ThreadAPI {
 
             // get stack trace for the carrier thread
             StackTraceElement[] stackTrace = map.get(carrier);
-            assertTrue(stackTrace != null);
+            assertNotNull(stackTrace);
             assertTrue(contains(stackTrace, "java.util.concurrent.ForkJoinPool"));
             assertFalse(contains(stackTrace, "java.lang.Object.wait"));
 
             // there should be no stack trace for the virtual thread
-            assertTrue(map.get(vthread) == null);
+            assertNull(map.get(vthread));
         }
     }
 
@@ -2065,7 +2047,7 @@ public class ThreadAPI {
      * Test Thread::getThreadGroup on virtual thread created by platform thread.
      */
     @Test
-    public void testThreadGroup1() throws Exception {
+    void testThreadGroup1() throws Exception {
         var thread = Thread.ofVirtual().unstarted(LockSupport::park);
         var vgroup = thread.getThreadGroup();
         thread.start();
@@ -2075,14 +2057,14 @@ public class ThreadAPI {
             LockSupport.unpark(thread);
             thread.join();
         }
-        assertTrue(thread.getThreadGroup() == null);
+        assertNull(thread.getThreadGroup());
     }
 
     /**
      * Test Thread::getThreadGroup on platform thread created by virtual thread.
      */
     @Test
-    public void testThreadGroup2() throws Exception {
+    void testThreadGroup2() throws Exception {
         VThreadRunner.run(() -> {
             ThreadGroup vgroup = Thread.currentThread().getThreadGroup();
             Thread child = new Thread(() -> { });
@@ -2096,7 +2078,7 @@ public class ThreadAPI {
      * created with 2-arg ThreadGroup constructor.
      */
     @Test
-    public void testThreadGroup3() throws Exception {
+    void testThreadGroup3() throws Exception {
         var ref = new AtomicReference<ThreadGroup>();
         var thread = Thread.startVirtualThread(() -> {
             ref.set(Thread.currentThread().getThreadGroup());
@@ -2124,7 +2106,7 @@ public class ThreadAPI {
      * created with 1-arg ThreadGroup constructor.
      */
     @Test
-    public void testThreadGroup4() throws Exception {
+    void testThreadGroup4() throws Exception {
         VThreadRunner.run(() -> {
             ThreadGroup vgroup = Thread.currentThread().getThreadGroup();
 
@@ -2148,7 +2130,7 @@ public class ThreadAPI {
      * Test Thread.enumerate(false).
      */
     @Test
-    public void testEnumerate1() throws Exception {
+    void testEnumerate1() throws Exception {
         VThreadRunner.run(() -> {
             ThreadGroup vgroup = Thread.currentThread().getThreadGroup();
             Thread[] threads = new Thread[100];
@@ -2161,7 +2143,7 @@ public class ThreadAPI {
      * Test Thread.enumerate(true).
      */
     @Test
-    public void testEnumerate2() throws Exception {
+    void testEnumerate2() throws Exception {
         VThreadRunner.run(() -> {
             ThreadGroup vgroup = Thread.currentThread().getThreadGroup();
             Thread[] threads = new Thread[100];
@@ -2174,15 +2156,15 @@ public class ThreadAPI {
      * Test equals and hashCode.
      */
     @Test
-    public void testEqualsAndHashCode() throws Exception {
+    void testEqualsAndHashCode() throws Exception {
         Thread vthread1 = Thread.ofVirtual().unstarted(LockSupport::park);
         Thread vthread2 = Thread.ofVirtual().unstarted(LockSupport::park);
 
         // unstarted
-        assertEquals(vthread1, vthread1);
-        assertNotEquals(vthread1, vthread2);
-        assertEquals(vthread2, vthread2);
-        assertNotEquals(vthread2, vthread1);
+        assertTrue(vthread1.equals(vthread1));
+        assertTrue(vthread2.equals(vthread2));
+        assertFalse(vthread1.equals(vthread2));
+        assertFalse(vthread2.equals(vthread1));
         int hc1 = vthread1.hashCode();
         int hc2 = vthread2.hashCode();
 
@@ -2190,10 +2172,10 @@ public class ThreadAPI {
         vthread2.start();
         try {
             // started, maybe running or parked
-            assertEquals(vthread1, vthread1);
-            assertNotEquals(vthread1, vthread2);
-            assertEquals(vthread2, vthread2);
-            assertNotEquals(vthread2, vthread1);
+            assertTrue(vthread1.equals(vthread1));
+            assertTrue(vthread2.equals(vthread2));
+            assertFalse(vthread1.equals(vthread2));
+            assertFalse(vthread2.equals(vthread1));
             assertTrue(vthread1.hashCode() == hc1);
             assertTrue(vthread2.hashCode() == hc2);
         } finally {
@@ -2204,10 +2186,10 @@ public class ThreadAPI {
         vthread2.join();
 
         // terminated
-        assertEquals(vthread1, vthread1);
-        assertNotEquals(vthread1, vthread2);
-        assertEquals(vthread2, vthread2);
-        assertNotEquals(vthread2, vthread1);
+        assertTrue(vthread1.equals(vthread1));
+        assertTrue(vthread2.equals(vthread2));
+        assertFalse(vthread1.equals(vthread2));
+        assertFalse(vthread2.equals(vthread1));
         assertTrue(vthread1.hashCode() == hc1);
         assertTrue(vthread2.hashCode() == hc2);
     }
@@ -2216,7 +2198,7 @@ public class ThreadAPI {
      * Test toString on unstarted thread.
      */
     @Test
-    public void testToString1() {
+    void testToString1() {
         Thread thread = Thread.ofVirtual().unstarted(() -> { });
         thread.setName("fred");
         assertTrue(thread.toString().contains("fred"));
@@ -2226,7 +2208,7 @@ public class ThreadAPI {
      * Test toString on running thread.
      */
     @Test
-    public void testToString2() throws Exception {
+    void testToString2() throws Exception {
         VThreadRunner.run(() -> {
             Thread me = Thread.currentThread();
             me.setName("fred");
@@ -2238,7 +2220,7 @@ public class ThreadAPI {
      * Test toString on parked thread.
      */
     @Test
-    public void testToString3() throws Exception {
+    void testToString3() throws Exception {
         Thread thread = Thread.ofVirtual().start(() -> {
             Thread me = Thread.currentThread();
             me.setName("fred");
@@ -2259,7 +2241,7 @@ public class ThreadAPI {
      * Test toString on terminated thread.
      */
     @Test
-    public void testToString4() throws Exception {
+    void testToString4() throws Exception {
         Thread thread = Thread.ofVirtual().start(() -> {
             Thread me = Thread.currentThread();
             me.setName("fred");
diff --git a/test/jdk/java/lang/Thread/virtual/ThreadLocals.java b/test/jdk/java/lang/Thread/virtual/ThreadLocals.java
index b2c748371f3..b6e930cdbab 100644
--- a/test/jdk/java/lang/Thread/virtual/ThreadLocals.java
+++ b/test/jdk/java/lang/Thread/virtual/ThreadLocals.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,14 +26,14 @@
  * @summary Test Virtual threads using thread locals
  * @library /test/lib
  * @enablePreview
- * @run testng ThreadLocals
+ * @run junit ThreadLocals
  */
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class ThreadLocals {
+class ThreadLocals {
     static final ThreadLocal<Object> LOCAL = new ThreadLocal<>();
     static final ThreadLocal<Object> INHERITED_LOCAL = new InheritableThreadLocal<>();
 
@@ -41,10 +41,10 @@ public class ThreadLocals {
      * Basic test of thread local set/get.
      */
     @Test
-    public void testThreadLocal1() throws Exception {
+    void testThreadLocal1() throws Exception {
         for (int i = 0; i < 10; i++) {
             VThreadRunner.run(() -> {
-                assertTrue(LOCAL.get() == null);
+                assertNull(LOCAL.get());
                 Object obj = new Object();
                 LOCAL.set(obj);
                 assertTrue(LOCAL.get() == obj);
@@ -56,9 +56,9 @@ public class ThreadLocals {
      * Test setting thread local before blocking operation.
      */
     @Test
-    public void testThreadLocal2() throws Exception {
+    void testThreadLocal2() throws Exception {
         VThreadRunner.run(() -> {
-            assertTrue(LOCAL.get() == null);
+            assertNull(LOCAL.get());
             Object obj = new Object();
             LOCAL.set(obj);
             try { Thread.sleep(100); } catch (InterruptedException e) { }
@@ -70,7 +70,7 @@ public class ThreadLocals {
      * Test Thread that cannot set values for its copy of thread-locals.
      */
     @Test
-    public void testThreadLocal3() throws Exception {
+    void testThreadLocal3() throws Exception {
         Object INITIAL_VALUE = new Object();
         ThreadLocal<Object> LOCAL2 = new ThreadLocal<>() {
             @Override
@@ -88,7 +88,7 @@ public class ThreadLocals {
         VThreadRunner.run(VThreadRunner.NO_THREAD_LOCALS, () -> {
             assertThrows(UnsupportedOperationException.class, () -> LOCAL.set(null));
             assertThrows(UnsupportedOperationException.class, () -> LOCAL.set(new Object()));
-            assertTrue(LOCAL.get() == null);
+            assertNull(LOCAL.get());
             LOCAL.remove();  // should not throw
 
             assertThrows(UnsupportedOperationException.class, () -> LOCAL2.set(null));
@@ -98,7 +98,7 @@ public class ThreadLocals {
 
             assertThrows(UnsupportedOperationException.class, () -> INHERITED_LOCAL.set(null));
             assertThrows(UnsupportedOperationException.class, () -> INHERITED_LOCAL.set(new Object()));
-            assertTrue(INHERITED_LOCAL.get() == null);
+            assertNull(INHERITED_LOCAL.get());
             INHERITED_LOCAL.remove();  // should not throw
 
             assertThrows(UnsupportedOperationException.class, () -> INHERITED_LOCAL2.set(null));
@@ -112,25 +112,25 @@ public class ThreadLocals {
      * Basic test of inheritable thread local set/get, no initial value inherited.
      */
     @Test
-    public void testInheritedThreadLocal1() throws Exception {
-        assertTrue(INHERITED_LOCAL.get() == null);
+    void testInheritedThreadLocal1() throws Exception {
+        assertNull(INHERITED_LOCAL.get());
         for (int i = 0; i < 10; i++) {
             VThreadRunner.run(() -> {
-                assertTrue(INHERITED_LOCAL.get() == null);
+                assertNull(INHERITED_LOCAL.get());
                 Object obj = new Object();
                 INHERITED_LOCAL.set(obj);
                 assertTrue(INHERITED_LOCAL.get() == obj);
             });
         }
-        assertTrue(INHERITED_LOCAL.get() == null);
+        assertNull(INHERITED_LOCAL.get());
     }
 
     /**
      * Test inheriting initial value of InheritableThreadLocal from platform thread.
      */
     @Test
-    public void testInheritedThreadLocal2() throws Exception {
-        assertTrue(INHERITED_LOCAL.get() == null);
+    void testInheritedThreadLocal2() throws Exception {
+        assertNull(INHERITED_LOCAL.get());
         var obj = new Object();
         INHERITED_LOCAL.set(obj);
         try {
@@ -146,8 +146,8 @@ public class ThreadLocals {
      * Test inheriting initial value of InheritableThreadLocal from virtual thread.
      */
     @Test
-    public void testInheritedThreadLocal3() throws Exception {
-        assertTrue(INHERITED_LOCAL.get() == null);
+    void testInheritedThreadLocal3() throws Exception {
+        assertNull(INHERITED_LOCAL.get());
         VThreadRunner.run(() -> {
             var obj = new Object();
             INHERITED_LOCAL.set(obj);
@@ -157,7 +157,7 @@ public class ThreadLocals {
             assertTrue(INHERITED_LOCAL.get() == obj);
 
         });
-        assertTrue(INHERITED_LOCAL.get() == null);
+        assertNull(INHERITED_LOCAL.get());
     }
 
     /**
@@ -165,14 +165,14 @@ public class ThreadLocals {
      * from platform thread.
      */
     @Test
-    public void testInheritedThreadLocal4() throws Exception {
-        assertTrue(INHERITED_LOCAL.get() == null);
+    void testInheritedThreadLocal4() throws Exception {
+        assertNull(INHERITED_LOCAL.get());
         var obj = new Object();
         INHERITED_LOCAL.set(obj);
         try {
             int characteristics = VThreadRunner.NO_INHERIT_THREAD_LOCALS;
             VThreadRunner.run(characteristics, () -> {
-                assertTrue(INHERITED_LOCAL.get() == null);
+                assertNull(INHERITED_LOCAL.get());
             });
         } finally {
             INHERITED_LOCAL.remove();
@@ -184,18 +184,18 @@ public class ThreadLocals {
      * from virtual thread.
      */
     @Test
-    public void testInheritedThreadLocal5() throws Exception {
-        assertTrue(INHERITED_LOCAL.get() == null);
+    void testInheritedThreadLocal5() throws Exception {
+        assertNull(INHERITED_LOCAL.get());
         VThreadRunner.run(() -> {
             var obj = new Object();
             INHERITED_LOCAL.set(obj);
             int characteristics = VThreadRunner.NO_INHERIT_THREAD_LOCALS;
             VThreadRunner.run(characteristics, () -> {
-                assertTrue(INHERITED_LOCAL.get() == null);
+                assertNull(INHERITED_LOCAL.get());
             });
             assertTrue(INHERITED_LOCAL.get() == obj);
 
         });
-        assertTrue(INHERITED_LOCAL.get() == null);
+        assertNull(INHERITED_LOCAL.get());
     }
 }
diff --git a/test/jdk/java/lang/Thread/virtual/TracePinnedThreads.java b/test/jdk/java/lang/Thread/virtual/TracePinnedThreads.java
index c112869fd4c..dd3156699a8 100644
--- a/test/jdk/java/lang/Thread/virtual/TracePinnedThreads.java
+++ b/test/jdk/java/lang/Thread/virtual/TracePinnedThreads.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,8 +28,8 @@
  * @requires vm.continuations
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm -Djdk.tracePinnedThreads=full TracePinnedThreads
- * @run testng/othervm -Djdk.tracePinnedThreads=short TracePinnedThreads
+ * @run junit/othervm -Djdk.tracePinnedThreads=full TracePinnedThreads
+ * @run junit/othervm -Djdk.tracePinnedThreads=short TracePinnedThreads
  */
 
 import java.io.ByteArrayOutputStream;
@@ -38,10 +38,10 @@ import java.time.Duration;
 import java.util.concurrent.locks.LockSupport;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class TracePinnedThreads {
+class TracePinnedThreads {
     static final Object lock = new Object();
 
     /**
@@ -62,7 +62,7 @@ public class TracePinnedThreads {
      * Test parking inside synchronized block.
      */
     @Test
-    public void testPinnedCausedBySynchronizedBlock() throws Exception {
+    void testPinnedCausedBySynchronizedBlock() throws Exception {
         String output = run(() -> {
             synchronized (lock) {
                 park();
@@ -76,7 +76,7 @@ public class TracePinnedThreads {
      * Test parking with native frame on stack.
      */
     @Test
-    public void testPinnedCausedByNativeMethod() throws Exception {
+    void testPinnedCausedByNativeMethod() throws Exception {
         System.loadLibrary("TracePinnedThreads");
         String output = run(() -> invokePark());
         assertContains(output, "(Native Method)");
diff --git a/test/jdk/java/lang/Thread/virtual/WaitNotify.java b/test/jdk/java/lang/Thread/virtual/WaitNotify.java
index ec6287f6f32..81f7f48b690 100644
--- a/test/jdk/java/lang/Thread/virtual/WaitNotify.java
+++ b/test/jdk/java/lang/Thread/virtual/WaitNotify.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,22 +26,22 @@
  * @summary Test virtual threads using Object.wait/notifyAll
  * @library /test/lib
  * @enablePreview
- * @run testng WaitNotify
+ * @run junit WaitNotify
  */
 
 import java.util.concurrent.Semaphore;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class WaitNotify {
+class WaitNotify {
 
     /**
      * Test virtual thread waits, notified by platform thread.
      */
     @Test
-    public void testWaitNotify1() throws Exception {
+    void testWaitNotify1() throws Exception {
         var lock = new Object();
         var ready = new Semaphore(0);
         var thread = Thread.ofVirtual().start(() -> {
@@ -64,7 +64,7 @@ public class WaitNotify {
      * Test platform thread waits, notified by virtual thread.
      */
     @Test
-    public void testWaitNotify2() throws Exception {
+    void testWaitNotify2() throws Exception {
         var lock = new Object();
         var ready = new Semaphore(0);
         var thread = Thread.ofVirtual().start(() -> {
@@ -84,7 +84,7 @@ public class WaitNotify {
      * Test virtual thread waits, notified by another virtual thread.
      */
     @Test
-    public void testWaitNotify3() throws Exception {
+    void testWaitNotify3() throws Exception {
         var lock = new Object();
         var ready = new Semaphore(0);
         var thread1 = Thread.ofVirtual().start(() -> {
@@ -109,7 +109,7 @@ public class WaitNotify {
      * Test interrupt status set when calling Object.wait.
      */
     @Test
-    public void testWaitNotify4() throws Exception {
+    void testWaitNotify4() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             t.interrupt();
@@ -130,7 +130,7 @@ public class WaitNotify {
      * Test interrupt when blocked in Object.wait.
      */
     @Test
-    public void testWaitNotify5() throws Exception {
+    void testWaitNotify5() throws Exception {
         VThreadRunner.run(() -> {
             Thread t = Thread.currentThread();
             scheduleInterrupt(t, 1000);
diff --git a/test/jdk/java/lang/ThreadGroup/BasicTests.java b/test/jdk/java/lang/ThreadGroup/BasicTests.java
index 4829a547848..2c6cf6dbca7 100644
--- a/test/jdk/java/lang/ThreadGroup/BasicTests.java
+++ b/test/jdk/java/lang/ThreadGroup/BasicTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -24,7 +24,7 @@
 /**
  * @test
  * @summary Unit tests for java.lang.ThreadGroup
- * @run testng BasicTests
+ * @run junit BasicTests
  */
 
 import java.lang.ref.WeakReference;
@@ -34,25 +34,25 @@ import java.util.Set;
 import java.util.concurrent.locks.LockSupport;
 import java.util.stream.Collectors;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class BasicTests {
+class BasicTests {
 
     @Test
-    public void testGetName1() {
+    void testGetName1() {
         ThreadGroup group = new ThreadGroup(null);
         assertTrue(group.getName() == null);
     }
 
     @Test
-    public void testGetName2() {
+    void testGetName2() {
         ThreadGroup group = new ThreadGroup("fred");
-        assertEquals(group.getName(), "fred");
+        assertEquals("fred", group.getName());
     }
 
     @Test
-    public void testGetParent() {
+    void testGetParent() {
         ThreadGroup group1 = new ThreadGroup("group1");
         ThreadGroup group2 = new ThreadGroup(group1, "group2");
         ThreadGroup group3 = new ThreadGroup(group2, "group3");
@@ -63,7 +63,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testParentOf() {
+    void testParentOf() {
         ThreadGroup group1 = new ThreadGroup("group1");
         ThreadGroup group2 = new ThreadGroup(group1, "group2");
         ThreadGroup group3 = new ThreadGroup(group2, "group3");
@@ -85,7 +85,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testActiveCount1() {
+    void testActiveCount1() {
         ThreadGroup group = new ThreadGroup("group");
         assertTrue(group.activeCount() == 0);
         TestThread thread = TestThread.start(group, "foo");
@@ -98,7 +98,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testActiveCount2() {
+    void testActiveCount2() {
         ThreadGroup group1 = new ThreadGroup("group1");
         ThreadGroup group2 = new ThreadGroup(group1, "group2");
         assertTrue(group1.activeCount() == 0);
@@ -124,7 +124,7 @@ public class BasicTests {
     }
 
     @Test
-    public void enumerateThreads1() {
+    void enumerateThreads1() {
         ThreadGroup group = new ThreadGroup("group");
         Thread[] threads = new Thread[100];
         assertTrue(group.enumerate(threads) == 0);
@@ -156,7 +156,7 @@ public class BasicTests {
     }
 
     @Test
-    public void enumerateThreads2() {
+    void enumerateThreads2() {
         ThreadGroup group1 = new ThreadGroup("group1");
         ThreadGroup group2 = new ThreadGroup(group1, "group2");
 
@@ -203,12 +203,12 @@ public class BasicTests {
             try {
                 Arrays.setAll(threads, i -> null);
                 assertTrue(group1.enumerate(threads) == 2);
-                assertEquals(toSet(threads, 2), Set.of(thread1, thread2));
+                assertEquals(Set.of(thread1, thread2), toSet(threads, 2));
                 assertTrue(threads[2] == null);
 
                 Arrays.setAll(threads, i -> null);
                 assertTrue(group1.enumerate(threads, true) == 2);
-                assertEquals(toSet(threads, 2), Set.of(thread1, thread2));
+                assertEquals(Set.of(thread1, thread2), toSet(threads, 2));
                 assertTrue(threads[2] == null);
 
                 Arrays.setAll(threads, i -> null);
@@ -261,7 +261,7 @@ public class BasicTests {
     }
 
     @Test
-    public void enumerateThreads3() {
+    void enumerateThreads3() {
         ThreadGroup group1 = new ThreadGroup("group1");
         ThreadGroup group2 = new ThreadGroup(group1, "group2");
         ThreadGroup group3 = new ThreadGroup(group2, "group3");
@@ -304,20 +304,20 @@ public class BasicTests {
             try {
                 Arrays.setAll(threads, i -> null);
                 assertTrue(group1.enumerate(threads) == 2);
-                assertEquals(toSet(threads, 2), Set.of(thread2, thread3));
+                assertEquals(Set.of(thread2, thread3), toSet(threads, 2));
 
                 Arrays.setAll(threads, i -> null);
                 assertTrue(group1.enumerate(threads, true) == 2);
-                assertEquals(toSet(threads, 2), Set.of(thread2, thread3));
+                assertEquals(Set.of(thread2, thread3), toSet(threads, 2));
                 assertTrue(group1.enumerate(threads, false) == 0);
 
                 Arrays.setAll(threads, i -> null);
                 assertTrue(group2.enumerate(threads) == 2);
-                assertEquals(toSet(threads, 2), Set.of(thread2, thread3));
+                assertEquals(Set.of(thread2, thread3), toSet(threads, 2));
 
                 Arrays.setAll(threads, i -> null);
                 assertTrue(group2.enumerate(threads, true) == 2);
-                assertEquals(toSet(threads, 2), Set.of(thread2, thread3));
+                assertEquals(Set.of(thread2, thread3), toSet(threads, 2));
 
                 Arrays.setAll(threads, i -> null);
                 assertTrue(group2.enumerate(threads, false) == 1);
@@ -391,7 +391,7 @@ public class BasicTests {
      * Test enumerate(Thread[]) with an array of insufficient size
      */
     @Test
-    public void enumerateThreads4() {
+    void enumerateThreads4() {
         ThreadGroup group = new ThreadGroup("group");
 
         // array too small
@@ -418,7 +418,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testActiveGroupCount() throws Exception {
+    void testActiveGroupCount() throws Exception {
         ThreadGroup group1 = new ThreadGroup("group1");
         assertTrue(group1.activeGroupCount() == 0);
 
@@ -444,7 +444,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testEnumerateGroups1() throws Exception {
+    void testEnumerateGroups1() throws Exception {
         ThreadGroup[] groups = new ThreadGroup[100];
 
         ThreadGroup group1 = new ThreadGroup("group1");
@@ -477,12 +477,12 @@ public class BasicTests {
 
         Arrays.setAll(groups, i -> null);
         assertTrue(group1.enumerate(groups) == 2);
-        assertEquals(toSet(groups, 2), Set.of(group2, group3));
+        assertEquals(Set.of(group2, group3), toSet(groups, 2));
         assertTrue(groups[2] == null);
 
         Arrays.setAll(groups, i -> null);
         assertTrue(group1.enumerate(groups, true) == 2);
-        assertEquals(toSet(groups, 2), Set.of(group2, group3));
+        assertEquals(Set.of(group2, group3), toSet(groups, 2));
         assertTrue(groups[2] == null);
 
         Arrays.setAll(groups, i -> null);
@@ -546,7 +546,7 @@ public class BasicTests {
      * Test enumerate(ThreadGroup[]) with an array of insufficient size
      */
     @Test
-    public void testEnumerateGroups2() throws Exception {
+    void testEnumerateGroups2() throws Exception {
         ThreadGroup group = new ThreadGroup("group");
         ThreadGroup child1 = new ThreadGroup(group, "child1");
         ThreadGroup child2 = new ThreadGroup(group,"child2");
@@ -568,7 +568,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testMaxPriority1() {
+    void testMaxPriority1() {
         ThreadGroup group = new ThreadGroup("group");
         final int maxPriority = group.getMaxPriority();
         assertTrue(maxPriority == Thread.currentThread().getThreadGroup().getMaxPriority());
@@ -592,7 +592,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testMaxPriority2() {
+    void testMaxPriority2() {
         ThreadGroup group1 = new ThreadGroup("group1");
         int maxPriority = group1.getMaxPriority();
         if (maxPriority > Thread.MIN_PRIORITY) {
@@ -630,7 +630,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testMaxPriority3() {
+    void testMaxPriority3() {
         ThreadGroup group = new ThreadGroup("group");
         if (group.getMaxPriority() > Thread.MIN_PRIORITY) {
             int maxPriority = Thread.MIN_PRIORITY + 1;
@@ -656,7 +656,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testInterrupt1() {
+    void testInterrupt1() {
         ThreadGroup group = new ThreadGroup("group");
         assertTrue(group.activeCount() == 0);
         TestThread thread = TestThread.start(group, "foo");
@@ -669,7 +669,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testInterrupt2() {
+    void testInterrupt2() {
         ThreadGroup group1 = new ThreadGroup("group1");
         ThreadGroup group2 = new ThreadGroup(group1, "group2");
         TestThread thread1 = TestThread.start(group1, "foo");
@@ -685,7 +685,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testInterrupt3() {
+    void testInterrupt3() {
         ThreadGroup group1 = new ThreadGroup("group1");
         ThreadGroup group2 = new ThreadGroup(group1, "group2");
         TestThread thread1 = TestThread.start(group1, "foo");
@@ -701,7 +701,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testDestroy() {
+    void testDestroy() {
         ThreadGroup group = new ThreadGroup("group");
         assertFalse(group.isDestroyed());
         group.destroy();  // does nothing
@@ -709,7 +709,7 @@ public class BasicTests {
     }
 
     @Test
-    public void testDaemon() {
+    void testDaemon() {
         boolean d = Thread.currentThread().getThreadGroup().isDaemon();
 
         ThreadGroup group1 = new ThreadGroup("group1");
@@ -727,68 +727,68 @@ public class BasicTests {
     }
 
     @Test
-    public void testList() {
+    void testList() {
         ThreadGroup group = new ThreadGroup("foo");
         group.list();
     }
 
     @Test
-    public void testSuspend() {
+    void testSuspend() {
         ThreadGroup group = new ThreadGroup("foo");
         assertThrows(UnsupportedOperationException.class, () -> group.suspend());
     }
 
     @Test
-    public void testResume() {
+    void testResume() {
         ThreadGroup group = new ThreadGroup("foo");
         assertThrows(UnsupportedOperationException.class, () -> group.resume());
     }
 
     @Test
-    public void testStop() {
+    void testStop() {
         ThreadGroup group = new ThreadGroup("foo");
         assertThrows(UnsupportedOperationException.class, () -> group.stop());
     }
 
     @Test
-    public void testNull1() {
+    void testNull1() {
         assertThrows(NullPointerException.class,
                      () -> new ThreadGroup(null, "group"));
     }
 
     @Test
-    public void testNull2() {
+    void testNull2() {
         ThreadGroup group = new ThreadGroup("group");
         assertThrows(NullPointerException.class,
                      () -> group.enumerate((Thread[]) null));
     }
 
     @Test
-    public void testNull3() {
+    void testNull3() {
         ThreadGroup group = new ThreadGroup("group");
         assertThrows(NullPointerException.class,
                      () -> group.enumerate((Thread[]) null, false));
     }
 
     @Test
-    public void testNull4() {
+    void testNull4() {
         ThreadGroup group = new ThreadGroup("group");
         assertThrows(NullPointerException.class,
                      () -> group.enumerate((ThreadGroup[]) null));
     }
 
     @Test
-    public void testNull5() {
+    void testNull5() {
         ThreadGroup group = new ThreadGroup("group");
         assertThrows(NullPointerException.class,
                      () -> group.enumerate((ThreadGroup[]) null, false));
     }
 
-    private <T> Set<T> toSet(T[] array, int len) {
+    private static <T> Set<T> toSet(T[] array, int len) {
         return Arrays.stream(array, 0, len).collect(Collectors.toSet());
     }
 
-    static class TestThread extends Thread {
+    private static class TestThread extends Thread {
         TestThread(ThreadGroup group, String name) {
             super(group, name);
         }
@@ -802,6 +802,7 @@ public class BasicTests {
         private volatile boolean done;
         private volatile boolean interrupted;
 
+        @Override
         public void run() {
             if (Thread.currentThread() != this)
                 throw new IllegalCallerException();
diff --git a/test/jdk/java/lang/management/ThreadMXBean/VirtualThreads.java b/test/jdk/java/lang/management/ThreadMXBean/VirtualThreads.java
index eff2b62ffae..e9bd48732d4 100644
--- a/test/jdk/java/lang/management/ThreadMXBean/VirtualThreads.java
+++ b/test/jdk/java/lang/management/ThreadMXBean/VirtualThreads.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
  * @summary Test java.lang.management.ThreadMXBean with virtual threads
  * @enablePreview
  * @modules java.base/java.lang:+open java.management
- * @run testng/othervm VirtualThreads
+ * @run junit/othervm VirtualThreads
  */
 
 /**
@@ -35,7 +35,7 @@
  * @requires vm.continuations
  * @enablePreview
  * @modules java.base/java.lang:+open java.management
- * @run testng/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations VirtualThreads
+ * @run junit/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations VirtualThreads
  */
 
 import java.lang.management.ManagementFactory;
@@ -51,9 +51,9 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.locks.LockSupport;
 
-import org.testng.SkipException;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assumptions.*;
 
 public class VirtualThreads {
 
@@ -62,7 +62,7 @@ public class VirtualThreads {
      * virtual threads.
      */
     @Test
-    public void testGetAllThreadIds() throws Exception {
+    void testGetAllThreadIds() throws Exception {
         Thread vthread = Thread.startVirtualThread(LockSupport::park);
         try {
             long[] tids = ManagementFactory.getThreadMXBean().getAllThreadIds();
@@ -83,7 +83,7 @@ public class VirtualThreads {
      * Test that ThreadMXBean.getThreadInfo(long) returns null for a virtual thread.
      */
     @Test
-    public void testGetThreadInfo1() throws Exception {
+    void testGetThreadInfo1() throws Exception {
         Thread vthread = Thread.startVirtualThread(LockSupport::park);
         try {
             long tid = vthread.threadId();
@@ -99,7 +99,7 @@ public class VirtualThreads {
      * thread with its own thread id.
      */
     @Test
-    public void testGetThreadInfo2() throws Exception {
+    void testGetThreadInfo2() throws Exception {
         runInVirtualThread(() -> {
             long tid = Thread.currentThread().threadId();
             ThreadInfo info = ManagementFactory.getThreadMXBean().getThreadInfo(tid);
@@ -112,9 +112,8 @@ public class VirtualThreads {
      * The stack frames of the virtual thread should not be returned.
      */
     @Test
-    public void testGetThreadInfo3() throws Exception {
-        if (!supportsCustomScheduler())
-            throw new SkipException("No support for custom schedulers");
+    void testGetThreadInfo3() throws Exception {
+        assumeTrue(supportsCustomScheduler(), "No support for custom schedulers");
         try (ExecutorService pool = Executors.newFixedThreadPool(1)) {
             var carrierRef = new AtomicReference<Thread>();
             Executor scheduler = (task) -> {
@@ -157,7 +156,7 @@ public class VirtualThreads {
      * elements that correspond to a virtual thread.
      */
     @Test
-    public void testGetThreadInfo4() throws Exception {
+    void testGetThreadInfo4() throws Exception {
         Thread vthread = Thread.startVirtualThread(LockSupport::park);
         try {
             long tid0 = Thread.currentThread().threadId();
@@ -175,7 +174,7 @@ public class VirtualThreads {
      * Test that ThreadMXBean.getThreadCpuTime(long) returns -1 for a virtual thread.
      */
     @Test
-    public void testGetThreadCpuTime1() {
+    void testGetThreadCpuTime1() {
         Thread vthread = Thread.startVirtualThread(LockSupport::park);
         try {
             long tid = vthread.threadId();
@@ -191,7 +190,7 @@ public class VirtualThreads {
      * virtual thread with its own thread id.
      */
     @Test
-    public void testGetThreadCpuTime2() throws Exception {
+    void testGetThreadCpuTime2() throws Exception {
         runInVirtualThread(() -> {
             long tid = Thread.currentThread().threadId();
             long cpuTime = ManagementFactory.getThreadMXBean().getThreadCpuTime(tid);
@@ -203,7 +202,7 @@ public class VirtualThreads {
      * Test that ThreadMXBean.getThreadUserTime(long) returns -1 for a virtual thread.
      */
     @Test
-    public void testGetThreadUserTime1() {
+    void testGetThreadUserTime1() {
         Thread vthread = Thread.startVirtualThread(LockSupport::park);
         try {
             long tid = vthread.threadId();
@@ -219,7 +218,7 @@ public class VirtualThreads {
      * virtual thread with its own thread id.
      */
     @Test
-    public void testGetThreadUserTime2() throws Exception {
+    void testGetThreadUserTime2() throws Exception {
         runInVirtualThread(() -> {
             long tid = Thread.currentThread().threadId();
             long userTime = ManagementFactory.getThreadMXBean().getThreadUserTime(tid);
@@ -231,10 +230,11 @@ public class VirtualThreads {
      * Test that ThreadMXBean::getCurrentThreadCpuTime throws UOE when invoked
      * on a virtual thread.
      */
-    @Test(expectedExceptions = { UnsupportedOperationException.class })
-    public void testGetCurrentThreadCpuTime() throws Exception {
+    @Test
+    void testGetCurrentThreadCpuTime() throws Exception {
         runInVirtualThread(() -> {
-            ManagementFactory.getThreadMXBean().getCurrentThreadCpuTime();
+            assertThrows(UnsupportedOperationException.class,
+                    () -> ManagementFactory.getThreadMXBean().getCurrentThreadCpuTime());
         });
     }
 
@@ -242,10 +242,11 @@ public class VirtualThreads {
      * Test that ThreadMXBean::getCurrentThreadUserTime throws UOE when
      * invoked on a virtual thread.
      */
-    @Test(expectedExceptions = { UnsupportedOperationException.class })
-    public void testGetCurrentThreadUserTime() throws Exception {
+    @Test
+    void testGetCurrentThreadUserTime() throws Exception {
         runInVirtualThread(() -> {
-            ManagementFactory.getThreadMXBean().getCurrentThreadUserTime();
+            assertThrows(UnsupportedOperationException.class,
+                    () -> ManagementFactory.getThreadMXBean().getCurrentThreadUserTime());
         });
     }
 
@@ -254,7 +255,7 @@ public class VirtualThreads {
      * invoked on a virtual thread.
      */
     @Test
-    public void testGetCurrentThreadAllocatedBytes() throws Exception {
+    void testGetCurrentThreadAllocatedBytes() throws Exception {
         runInVirtualThread(() -> {
             long allocated = ManagementFactory.getPlatformMXBean(com.sun.management.ThreadMXBean.class)
                     .getCurrentThreadAllocatedBytes();
diff --git a/test/jdk/java/net/vthread/BlockingSocketOps.java b/test/jdk/java/net/vthread/BlockingSocketOps.java
index 8a69c721eb6..e804c7d9e44 100644
--- a/test/jdk/java/net/vthread/BlockingSocketOps.java
+++ b/test/jdk/java/net/vthread/BlockingSocketOps.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
  * @summary Test virtual threads doing blocking I/O on java.net sockets
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm BlockingSocketOps
+ * @run junit BlockingSocketOps
  */
 
 /**
@@ -36,7 +36,7 @@
  *    the I/O poller configured to use direct registration
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm -Djdk.useDirectRegister BlockingSocketOps
+ * @run junit/othervm -Djdk.useDirectRegister BlockingSocketOps
  */
 
 /**
@@ -44,7 +44,7 @@
  * @requires vm.continuations
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations BlockingSocketOps
+ * @run junit/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations BlockingSocketOps
  */
 
 import java.io.Closeable;
@@ -62,16 +62,16 @@ import java.net.SocketException;
 import java.net.SocketTimeoutException;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class BlockingSocketOps {
+class BlockingSocketOps {
 
     /**
      * Socket read/write, no blocking.
      */
     @Test
-    public void testSocketReadWrite1() throws Exception {
+    void testSocketReadWrite1() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 Socket s1 = connection.socket1();
@@ -94,7 +94,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in read.
      */
     @Test
-    public void testSocketRead1() throws Exception {
+    void testSocketRead1() throws Exception {
         testSocketRead(0);
     }
 
@@ -102,7 +102,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in timed read.
      */
     @Test
-    public void testSocketRead2() throws Exception {
+    void testSocketRead2() throws Exception {
         testSocketRead(60_000);
     }
 
@@ -132,7 +132,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in write.
      */
     @Test
-    public void testSocketWrite1() throws Exception {
+    void testSocketWrite1() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 Socket s1 = connection.socket1();
@@ -161,7 +161,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in read, peer closes connection gracefully.
      */
     @Test
-    public void testSocketReadPeerClose1() throws Exception {
+    void testSocketReadPeerClose1() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 Socket s1 = connection.socket1();
@@ -181,7 +181,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in read, peer closes connection abruptly.
      */
     @Test
-    public void testSocketReadPeerClose2() throws Exception {
+    void testSocketReadPeerClose2() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 Socket s1 = connection.socket1();
@@ -206,7 +206,7 @@ public class BlockingSocketOps {
      * Socket close while virtual thread blocked in read.
      */
     @Test
-    public void testSocketReadAsyncClose1() throws Exception {
+    void testSocketReadAsyncClose1() throws Exception {
         testSocketReadAsyncClose(0);
     }
 
@@ -214,7 +214,7 @@ public class BlockingSocketOps {
      * Socket close while virtual thread blocked in timed read.
      */
     @Test
-    public void testSocketReadAsyncClose2() throws Exception {
+    void testSocketReadAsyncClose2() throws Exception {
         testSocketReadAsyncClose(0);
     }
 
@@ -242,7 +242,7 @@ public class BlockingSocketOps {
      * Virtual thread interrupted while blocked in Socket read.
      */
     @Test
-    public void testSocketReadInterrupt1() throws Exception {
+    void testSocketReadInterrupt1() throws Exception {
         testSocketReadInterrupt(0);
     }
 
@@ -250,7 +250,7 @@ public class BlockingSocketOps {
      * Virtual thread interrupted while blocked in Socket read with timeout
      */
     @Test
-    public void testSocketReadInterrupt2() throws Exception {
+    void testSocketReadInterrupt2() throws Exception {
         testSocketReadInterrupt(60_000);
     }
 
@@ -283,7 +283,7 @@ public class BlockingSocketOps {
      * Socket close while virtual thread blocked in write.
      */
     @Test
-    public void testSocketWriteAsyncClose() throws Exception {
+    void testSocketWriteAsyncClose() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 Socket s = connection.socket1();
@@ -307,7 +307,7 @@ public class BlockingSocketOps {
      * Virtual thread interrupted while blocked in Socket write.
      */
     @Test
-    public void testSocketWriteInterrupt() throws Exception {
+    void testSocketWriteInterrupt() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 Socket s = connection.socket1();
@@ -335,7 +335,7 @@ public class BlockingSocketOps {
      * Virtual thread reading urgent data when SO_OOBINLINE is enabled.
      */
     @Test
-    public void testSocketReadUrgentData() throws Exception {
+    void testSocketReadUrgentData() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 Socket s1 = connection.socket1();
@@ -367,7 +367,7 @@ public class BlockingSocketOps {
      * ServerSocket accept, no blocking.
      */
     @Test
-    public void testServerSocketAccept1() throws Exception {
+    void testServerSocketAccept1() throws Exception {
         VThreadRunner.run(() -> {
             try (var listener = new ServerSocket()) {
                 InetAddress loopback = InetAddress.getLoopbackAddress();
@@ -388,7 +388,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in accept.
      */
     @Test
-    public void testServerSocketAccept2() throws Exception {
+    void testServerSocketAccept2() throws Exception {
         testServerSocketAccept(0);
     }
 
@@ -396,7 +396,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in timed accept.
      */
     @Test
-    public void testServerSocketAccept3() throws Exception {
+    void testServerSocketAccept3() throws Exception {
         testServerSocketAccept(60_000);
     }
 
@@ -426,7 +426,7 @@ public class BlockingSocketOps {
      * ServerSocket close while virtual thread blocked in accept.
      */
     @Test
-    public void testServerSocketAcceptAsyncClose1() throws Exception {
+    void testServerSocketAcceptAsyncClose1() throws Exception {
         testServerSocketAcceptAsyncClose(0);
     }
 
@@ -434,7 +434,7 @@ public class BlockingSocketOps {
      * ServerSocket close while virtual thread blocked in timed accept.
      */
     @Test
-    public void testServerSocketAcceptAsyncClose2() throws Exception {
+    void testServerSocketAcceptAsyncClose2() throws Exception {
         testServerSocketAcceptAsyncClose(60_000);
     }
 
@@ -463,7 +463,7 @@ public class BlockingSocketOps {
      * Virtual thread interrupted while blocked in ServerSocket accept.
      */
     @Test
-    public void testServerSocketAcceptInterrupt1() throws Exception {
+    void testServerSocketAcceptInterrupt1() throws Exception {
         testServerSocketAcceptInterrupt(0);
     }
 
@@ -471,7 +471,7 @@ public class BlockingSocketOps {
      * Virtual thread interrupted while blocked in ServerSocket accept with timeout.
      */
     @Test
-    public void testServerSocketAcceptInterrupt2() throws Exception {
+    void testServerSocketAcceptInterrupt2() throws Exception {
         testServerSocketAcceptInterrupt(60_000);
     }
 
@@ -504,7 +504,7 @@ public class BlockingSocketOps {
      * DatagramSocket receive/send, no blocking.
      */
     @Test
-    public void testDatagramSocketSendReceive1() throws Exception {
+    void testDatagramSocketSendReceive1() throws Exception {
         VThreadRunner.run(() -> {
             try (DatagramSocket s1 = new DatagramSocket(null);
                  DatagramSocket s2 = new DatagramSocket(null)) {
@@ -523,7 +523,7 @@ public class BlockingSocketOps {
                 byte[] ba = new byte[100];
                 DatagramPacket p2 = new DatagramPacket(ba, ba.length);
                 s2.receive(p2);
-                assertEquals(p2.getSocketAddress(), s1.getLocalSocketAddress());
+                assertEquals(s1.getLocalSocketAddress(), p2.getSocketAddress());
                 assertTrue(ba[0] == 'X');
             }
         });
@@ -533,7 +533,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in DatagramSocket receive.
      */
     @Test
-    public void testDatagramSocketSendReceive2() throws Exception {
+    void testDatagramSocketSendReceive2() throws Exception {
         testDatagramSocketSendReceive(0);
     }
 
@@ -541,7 +541,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in DatagramSocket receive with timeout.
      */
     @Test
-    public void testDatagramSocketSendReceive3() throws Exception {
+    void testDatagramSocketSendReceive3() throws Exception {
         testDatagramSocketSendReceive(60_000);
     }
 
@@ -567,7 +567,7 @@ public class BlockingSocketOps {
                 byte[] ba = new byte[100];
                 DatagramPacket p2 = new DatagramPacket(ba, ba.length);
                 s2.receive(p2);
-                assertEquals(p2.getSocketAddress(), s1.getLocalSocketAddress());
+                assertEquals(s1.getLocalSocketAddress(), p2.getSocketAddress());
                 assertTrue(ba[0] == 'X');
             }
         });
@@ -577,7 +577,7 @@ public class BlockingSocketOps {
      * Virtual thread blocks in DatagramSocket receive that times out.
      */
     @Test
-    public void testDatagramSocketReceiveTimeout() throws Exception {
+    void testDatagramSocketReceiveTimeout() throws Exception {
         VThreadRunner.run(() -> {
             try (DatagramSocket s = new DatagramSocket(null)) {
                 InetAddress lh = InetAddress.getLoopbackAddress();
@@ -597,7 +597,7 @@ public class BlockingSocketOps {
      * DatagramSocket close while virtual thread blocked in receive.
      */
     @Test
-    public void testDatagramSocketReceiveAsyncClose1() throws Exception {
+    void testDatagramSocketReceiveAsyncClose1() throws Exception {
         testDatagramSocketReceiveAsyncClose(0);
     }
 
@@ -605,7 +605,7 @@ public class BlockingSocketOps {
      * DatagramSocket close while virtual thread blocked with timeout.
      */
     @Test
-    public void testDatagramSocketReceiveAsyncClose2() throws Exception {
+    void testDatagramSocketReceiveAsyncClose2() throws Exception {
         testDatagramSocketReceiveAsyncClose(60_000);
     }
 
@@ -636,7 +636,7 @@ public class BlockingSocketOps {
      * Virtual thread interrupted while blocked in DatagramSocket receive.
      */
     @Test
-    public void testDatagramSocketReceiveInterrupt1() throws Exception {
+    void testDatagramSocketReceiveInterrupt1() throws Exception {
         testDatagramSocketReceiveInterrupt(0);
     }
 
@@ -644,7 +644,7 @@ public class BlockingSocketOps {
      * Virtual thread interrupted while blocked in DatagramSocket receive with timeout.
      */
     @Test
-    public void testDatagramSocketReceiveInterrupt2() throws Exception {
+    void testDatagramSocketReceiveInterrupt2() throws Exception {
         testDatagramSocketReceiveInterrupt(60_000);
     }
 
diff --git a/test/jdk/java/nio/channels/vthread/BlockingChannelOps.java b/test/jdk/java/nio/channels/vthread/BlockingChannelOps.java
index a7b24779766..8fb878987b7 100644
--- a/test/jdk/java/nio/channels/vthread/BlockingChannelOps.java
+++ b/test/jdk/java/nio/channels/vthread/BlockingChannelOps.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
  * @summary Test virtual threads doing blocking I/O on NIO channels
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm BlockingChannelOps
+ * @run junit BlockingChannelOps
  */
 
 /**
@@ -36,7 +36,7 @@
  *    the I/O poller configured to use direct registration
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm -Djdk.useDirectRegister BlockingChannelOps
+ * @run junit/othervm -Djdk.useDirectRegister BlockingChannelOps
  */
 
 /**
@@ -44,7 +44,7 @@
  * @requires vm.continuations
  * @enablePreview
  * @library /test/lib
- * @run testng/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations BlockingChannelOps
+ * @run junit/othervm -XX:+UnlockExperimentalVMOptions -XX:-VMContinuations BlockingChannelOps
  */
 
 import java.io.Closeable;
@@ -67,16 +67,16 @@ import java.nio.channels.SocketChannel;
 import java.nio.channels.WritableByteChannel;
 
 import jdk.test.lib.thread.VThreadRunner;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class BlockingChannelOps {
+class BlockingChannelOps {
 
     /**
      * SocketChannel read/write, no blocking.
      */
     @Test
-    public void testSocketChannelReadWrite1() throws Exception {
+    void testSocketChannelReadWrite1() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 SocketChannel sc1 = connection.channel1();
@@ -100,7 +100,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in SocketChannel read.
      */
     @Test
-    public void testSocketChannelRead() throws Exception {
+    void testSocketChannelRead() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 SocketChannel sc1 = connection.channel1();
@@ -123,7 +123,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in SocketChannel write.
      */
     @Test
-    public void testSocketChannelWrite() throws Exception {
+    void testSocketChannelWrite() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 SocketChannel sc1 = connection.channel1();
@@ -151,7 +151,7 @@ public class BlockingChannelOps {
      * SocketChannel close while virtual thread blocked in read.
      */
     @Test
-    public void testSocketChannelReadAsyncClose() throws Exception {
+    void testSocketChannelReadAsyncClose() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 SocketChannel sc = connection.channel1();
@@ -168,7 +168,7 @@ public class BlockingChannelOps {
      * Virtual thread interrupted while blocked in SocketChannel read.
      */
     @Test
-    public void testSocketChannelReadInterrupt() throws Exception {
+    void testSocketChannelReadInterrupt() throws Exception {
         VThreadRunner.run(() -> {
             try (var connection = new Connection()) {
                 SocketChannel sc = connection.channel1();
@@ -191,7 +191,7 @@ public class BlockingChannelOps {
      * SocketChannel close while virtual thread blocked in write.
      */
     @Test
-    public void testSocketChannelWriteAsyncClose() throws Exception {
+    void testSocketChannelWriteAsyncClose() throws Exception {
         VThreadRunner.run(() -> {
             boolean retry = true;
             while (retry) {
@@ -222,7 +222,7 @@ public class BlockingChannelOps {
      * Virtual thread interrupted while blocked in SocketChannel write.
      */
     @Test
-    public void testSocketChannelWriteInterrupt() throws Exception {
+    void testSocketChannelWriteInterrupt() throws Exception {
         VThreadRunner.run(() -> {
             boolean retry = true;
             while (retry) {
@@ -256,7 +256,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in SocketChannel adaptor read.
      */
     @Test
-    public void testSocketAdaptorRead1() throws Exception {
+    void testSocketAdaptorRead1() throws Exception {
         testSocketAdaptorRead(0);
     }
 
@@ -264,7 +264,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in SocketChannel adaptor read with timeout.
      */
     @Test
-    public void testSocketAdaptorRead2() throws Exception {
+    void testSocketAdaptorRead2() throws Exception {
         testSocketAdaptorRead(60_000);
     }
 
@@ -293,7 +293,7 @@ public class BlockingChannelOps {
      * ServerSocketChannel accept, no blocking.
      */
     @Test
-    public void testServerSocketChannelAccept1() throws Exception {
+    void testServerSocketChannelAccept1() throws Exception {
         VThreadRunner.run(() -> {
             try (var ssc = ServerSocketChannel.open()) {
                 ssc.bind(new InetSocketAddress(InetAddress.getLoopbackAddress(), 0));
@@ -310,7 +310,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in ServerSocketChannel accept.
      */
     @Test
-    public void testServerSocketChannelAccept2() throws Exception {
+    void testServerSocketChannelAccept2() throws Exception {
         VThreadRunner.run(() -> {
             try (var ssc = ServerSocketChannel.open()) {
                 ssc.bind(new InetSocketAddress(InetAddress.getLoopbackAddress(), 0));
@@ -331,7 +331,7 @@ public class BlockingChannelOps {
      * SeverSocketChannel close while virtual thread blocked in accept.
      */
     @Test
-    public void testServerSocketChannelAcceptAsyncClose() throws Exception {
+    void testServerSocketChannelAcceptAsyncClose() throws Exception {
         VThreadRunner.run(() -> {
             try (var ssc = ServerSocketChannel.open()) {
                 InetAddress lh = InetAddress.getLoopbackAddress();
@@ -350,7 +350,7 @@ public class BlockingChannelOps {
      * Virtual thread interrupted while blocked in ServerSocketChannel accept.
      */
     @Test
-    public void testServerSocketChannelAcceptInterrupt() throws Exception {
+    void testServerSocketChannelAcceptInterrupt() throws Exception {
         VThreadRunner.run(() -> {
             try (var ssc = ServerSocketChannel.open()) {
                 InetAddress lh = InetAddress.getLoopbackAddress();
@@ -375,7 +375,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in ServerSocketChannel adaptor accept.
      */
     @Test
-    public void testSocketChannelAdaptorAccept1() throws Exception {
+    void testSocketChannelAdaptorAccept1() throws Exception {
         testSocketChannelAdaptorAccept(0);
     }
 
@@ -383,7 +383,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in ServerSocketChannel adaptor accept with timeout.
      */
     @Test
-    public void testSocketChannelAdaptorAccept2() throws Exception {
+    void testSocketChannelAdaptorAccept2() throws Exception {
         testSocketChannelAdaptorAccept(60_000);
     }
 
@@ -410,7 +410,7 @@ public class BlockingChannelOps {
      * DatagramChannel receive/send, no blocking.
      */
     @Test
-    public void testDatagramChannelSendReceive1() throws Exception {
+    void testDatagramChannelSendReceive1() throws Exception {
         VThreadRunner.run(() -> {
             try (DatagramChannel dc1 = DatagramChannel.open();
                  DatagramChannel dc2 = DatagramChannel.open()) {
@@ -435,7 +435,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in DatagramChannel receive.
      */
     @Test
-    public void testDatagramChannelSendReceive2() throws Exception {
+    void testDatagramChannelSendReceive2() throws Exception {
         VThreadRunner.run(() -> {
             try (DatagramChannel dc1 = DatagramChannel.open();
                  DatagramChannel dc2 = DatagramChannel.open()) {
@@ -459,7 +459,7 @@ public class BlockingChannelOps {
      * DatagramChannel close while virtual thread blocked in receive.
      */
     @Test
-    public void testDatagramChannelReceiveAsyncClose() throws Exception {
+    void testDatagramChannelReceiveAsyncClose() throws Exception {
         VThreadRunner.run(() -> {
             try (DatagramChannel dc = DatagramChannel.open()) {
                 InetAddress lh = InetAddress.getLoopbackAddress();
@@ -477,7 +477,7 @@ public class BlockingChannelOps {
      * Virtual thread interrupted while blocked in DatagramChannel receive.
      */
     @Test
-    public void testDatagramChannelReceiveInterrupt() throws Exception {
+    void testDatagramChannelReceiveInterrupt() throws Exception {
         VThreadRunner.run(() -> {
             try (DatagramChannel dc = DatagramChannel.open()) {
                 InetAddress lh = InetAddress.getLoopbackAddress();
@@ -501,7 +501,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in DatagramSocket adaptor receive.
      */
     @Test
-    public void testDatagramSocketAdaptorReceive1() throws Exception {
+    void testDatagramSocketAdaptorReceive1() throws Exception {
         testDatagramSocketAdaptorReceive(0);
     }
 
@@ -509,7 +509,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in DatagramSocket adaptor receive with timeout.
      */
     @Test
-    public void testDatagramSocketAdaptorReceive2() throws Exception {
+    void testDatagramSocketAdaptorReceive2() throws Exception {
         testDatagramSocketAdaptorReceive(60_1000);
     }
 
@@ -540,7 +540,7 @@ public class BlockingChannelOps {
      * DatagramChannel close while virtual thread blocked in adaptor receive.
      */
     @Test
-    public void testDatagramSocketAdaptorReceiveAsyncClose1() throws Exception {
+    void testDatagramSocketAdaptorReceiveAsyncClose1() throws Exception {
         testDatagramSocketAdaptorReceiveAsyncClose(0);
     }
 
@@ -549,7 +549,7 @@ public class BlockingChannelOps {
      * with timeout.
      */
     @Test
-    public void testDatagramSocketAdaptorReceiveAsyncClose2() throws Exception {
+    void testDatagramSocketAdaptorReceiveAsyncClose2() throws Exception {
         testDatagramSocketAdaptorReceiveAsyncClose(60_1000);
     }
 
@@ -576,7 +576,7 @@ public class BlockingChannelOps {
      * Virtual thread interrupted while blocked in DatagramSocket adaptor receive.
      */
     @Test
-    public void testDatagramSocketAdaptorReceiveInterrupt1() throws Exception {
+    void testDatagramSocketAdaptorReceiveInterrupt1() throws Exception {
         testDatagramSocketAdaptorReceiveInterrupt(0);
     }
 
@@ -585,7 +585,7 @@ public class BlockingChannelOps {
      * with timeout.
      */
     @Test
-    public void testDatagramSocketAdaptorReceiveInterrupt2() throws Exception {
+    void testDatagramSocketAdaptorReceiveInterrupt2() throws Exception {
         testDatagramSocketAdaptorReceiveInterrupt(60_1000);
     }
 
@@ -618,7 +618,7 @@ public class BlockingChannelOps {
      * Pipe read/write, no blocking.
      */
     @Test
-    public void testPipeReadWrite1() throws Exception {
+    void testPipeReadWrite1() throws Exception {
         VThreadRunner.run(() -> {
             Pipe p = Pipe.open();
             try (Pipe.SinkChannel sink = p.sink();
@@ -642,7 +642,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in Pipe.SourceChannel read.
      */
     @Test
-    public void testPipeReadWrite2() throws Exception {
+    void testPipeReadWrite2() throws Exception {
         VThreadRunner.run(() -> {
             Pipe p = Pipe.open();
             try (Pipe.SinkChannel sink = p.sink();
@@ -665,7 +665,7 @@ public class BlockingChannelOps {
      * Virtual thread blocks in Pipe.SinkChannel write.
      */
     @Test
-    public void testPipeReadWrite3() throws Exception {
+    void testPipeReadWrite3() throws Exception {
         VThreadRunner.run(() -> {
             Pipe p = Pipe.open();
             try (Pipe.SinkChannel sink = p.sink();
@@ -693,7 +693,7 @@ public class BlockingChannelOps {
      * Pipe.SourceChannel close while virtual thread blocked in read.
      */
     @Test
-    public void testPipeReadAsyncClose() throws Exception {
+    void testPipeReadAsyncClose() throws Exception {
         VThreadRunner.run(() -> {
             Pipe p = Pipe.open();
             try (Pipe.SinkChannel sink = p.sink();
@@ -711,7 +711,7 @@ public class BlockingChannelOps {
      * Virtual thread interrupted while blocked in Pipe.SourceChannel read.
      */
     @Test
-    public void testPipeReadInterrupt() throws Exception {
+    void testPipeReadInterrupt() throws Exception {
         VThreadRunner.run(() -> {
             Pipe p = Pipe.open();
             try (Pipe.SinkChannel sink = p.sink();
@@ -735,7 +735,7 @@ public class BlockingChannelOps {
      * Pipe.SinkChannel close while virtual thread blocked in write.
      */
     @Test
-    public void testPipeWriteAsyncClose() throws Exception {
+    void testPipeWriteAsyncClose() throws Exception {
         VThreadRunner.run(() -> {
             boolean retry = true;
             while (retry) {
@@ -767,7 +767,7 @@ public class BlockingChannelOps {
      * Virtual thread interrupted while blocked in Pipe.SinkChannel write.
      */
     @Test
-    public void testPipeWriteInterrupt() throws Exception {
+    void testPipeWriteInterrupt() throws Exception {
         VThreadRunner.run(() -> {
             boolean retry = true;
             while (retry) {
diff --git a/test/jdk/java/util/concurrent/ThreadPerTaskExecutor/ThreadPerTaskExecutorTest.java b/test/jdk/java/util/concurrent/ThreadPerTaskExecutor/ThreadPerTaskExecutorTest.java
index 753d2a256fc..caaa2a23bf8 100644
--- a/test/jdk/java/util/concurrent/ThreadPerTaskExecutor/ThreadPerTaskExecutorTest.java
+++ b/test/jdk/java/util/concurrent/ThreadPerTaskExecutor/ThreadPerTaskExecutorTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,13 +25,13 @@
  * @test id=platform
  * @summary Basic tests for new thread-per-task executors
  * @enablePreview
- * @run testng/othervm -DthreadFactory=platform ThreadPerTaskExecutorTest
+ * @run junit/othervm -DthreadFactory=platform ThreadPerTaskExecutorTest
  */
 
 /*
  * @test id=virtual
  * @enablePreview
- * @run testng/othervm -DthreadFactory=virtual ThreadPerTaskExecutorTest
+ * @run junit/othervm -DthreadFactory=virtual ThreadPerTaskExecutorTest
  */
 
 import java.time.Duration;
@@ -45,32 +45,29 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import static java.util.concurrent.Future.State.*;
 
-import org.testng.annotations.AfterClass;
-import org.testng.annotations.BeforeClass;
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class ThreadPerTaskExecutorTest {
+class ThreadPerTaskExecutorTest {
     // long running interruptible task
     private static final Callable<Void> SLEEP_FOR_A_DAY = () -> {
         Thread.sleep(Duration.ofDays(1));
         return null;
     };
 
-    private ScheduledExecutorService scheduler;
-    private Object[][] threadFactories;
+    private static ScheduledExecutorService scheduler;
+    private static List<ThreadFactory> threadFactories;
 
-    @BeforeClass
-    public void setUp() throws Exception {
-        ThreadFactory factory = (task) -> {
-            Thread thread = new Thread(task);
-            thread.setDaemon(true);
-            return thread;
-        };
-        this.scheduler = Executors.newSingleThreadScheduledExecutor(factory);
+    @BeforeAll
+    static void setup() throws Exception {
+        scheduler = Executors.newSingleThreadScheduledExecutor();
 
         // thread factories
         String value = System.getProperty("threadFactory");
@@ -80,27 +77,21 @@ public class ThreadPerTaskExecutorTest {
         if (value == null || value.equals("virtual"))
             list.add(Thread.ofVirtual().factory());
         assertTrue(list.size() > 0, "No thread factories for tests");
-        this.threadFactories = list.stream()
-                .map(f -> new Object[] { f })
-                .toArray(Object[][]::new);
+        threadFactories = list;
     }
 
-    @AfterClass
-    public void tearDown() {
+    @AfterAll
+    static void shutdown() {
         scheduler.shutdown();
     }
 
-    @DataProvider(name = "factories")
-    public Object[][] factories() {
-        return threadFactories;
+    private static Stream<ThreadFactory> factories() {
+        return threadFactories.stream();
     }
 
-    @DataProvider(name = "executors")
-    public Object[][] executors() {
-        return Arrays.stream(threadFactories)
-                .map(f -> Executors.newThreadPerTaskExecutor((ThreadFactory) f[0]))
-                .map(e -> new Object[] { e })
-                .toArray(Object[][]::new);
+    private static Stream<ExecutorService> executors() {
+        return threadFactories.stream()
+                .map(f -> Executors.newThreadPerTaskExecutor(f));
     }
 
     /**
@@ -114,8 +105,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test that a thread is created for each task.
      */
-    @Test(dataProvider = "factories")
-    public void testThreadPerTask(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testThreadPerTask(ThreadFactory factory) throws Exception {
         final int NUM_TASKS = 100;
         AtomicInteger threadCount = new AtomicInteger();
 
@@ -135,7 +127,7 @@ public class ThreadPerTaskExecutorTest {
         }
 
         assertTrue(executor.isTerminated());
-        assertEquals(threadCount.get(), NUM_TASKS);
+        assertEquals(NUM_TASKS, threadCount.get());
         for (int i=0; i<NUM_TASKS; i++) {
             Future<Integer> future = futures.get(i);
             assertEquals((int) future.get(), i);
@@ -146,7 +138,7 @@ public class ThreadPerTaskExecutorTest {
      * Test that newThreadPerTaskExecutor uses the specified thread factory.
      */
     @Test
-    public void testThreadFactory() throws Exception {
+    void testThreadFactory() throws Exception {
         var ref1 = new AtomicReference<Thread>();
         var ref2 = new AtomicReference<Thread>();
         ThreadFactory factory = task -> {
@@ -166,8 +158,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test shutdown.
      */
-    @Test(dataProvider = "executors")
-    public void testShutdown(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testShutdown(ExecutorService executor) throws Exception {
         try (executor) {
             assertFalse(executor.isShutdown());
             assertFalse(executor.isTerminated());
@@ -188,8 +181,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test shutdownNow.
      */
-    @Test(dataProvider = "executors")
-    public void testShutdownNow(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testShutdownNow(ExecutorService executor) throws Exception {
         try (executor) {
             assertFalse(executor.isShutdown());
             assertFalse(executor.isTerminated());
@@ -201,7 +195,7 @@ public class ThreadPerTaskExecutorTest {
                 assertTrue(executor.isShutdown());
                 assertTrue(tasks.isEmpty());
 
-                Throwable e = expectThrows(ExecutionException.class, result::get);
+                Throwable e = assertThrows(ExecutionException.class, result::get);
                 assertTrue(e.getCause() instanceof InterruptedException);
 
                 assertTrue(executor.awaitTermination(3, TimeUnit.SECONDS));
@@ -215,8 +209,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test close with no threads running.
      */
-    @Test(dataProvider = "executors")
-    public void testClose1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testClose1(ExecutorService executor) throws Exception {
         executor.close();
         assertTrue(executor.isShutdown());
         assertTrue(executor.isTerminated());
@@ -226,8 +221,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test close with threads running.
      */
-    @Test(dataProvider = "executors")
-    public void testClose2(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testClose2(ExecutorService executor) throws Exception {
         Future<String> future;
         try (executor) {
             future = executor.submit(() -> {
@@ -244,8 +240,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Invoke close with interrupt status set, should cancel task.
      */
-    @Test(dataProvider = "executors")
-    public void testClose3(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testClose3(ExecutorService executor) throws Exception {
         Future<?> future;
         try (executor) {
             future = executor.submit(SLEEP_FOR_A_DAY);
@@ -257,14 +254,15 @@ public class ThreadPerTaskExecutorTest {
         assertTrue(executor.isShutdown());
         assertTrue(executor.isTerminated());
         assertTrue(executor.awaitTermination(10,  TimeUnit.MILLISECONDS));
-        expectThrows(ExecutionException.class, future::get);
+        assertThrows(ExecutionException.class, future::get);
     }
 
     /**
      * Interrupt thread blocked in close.
      */
-    @Test(dataProvider = "executors")
-    public void testClose4(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testClose4(ExecutorService executor) throws Exception {
         Future<?> future;
         try (executor) {
             future = executor.submit(SLEEP_FOR_A_DAY);
@@ -275,14 +273,15 @@ public class ThreadPerTaskExecutorTest {
         assertTrue(executor.isShutdown());
         assertTrue(executor.isTerminated());
         assertTrue(executor.awaitTermination(10,  TimeUnit.MILLISECONDS));
-        expectThrows(ExecutionException.class, future::get);
+        assertThrows(ExecutionException.class, future::get);
     }
 
     /**
      * Close executor that is already closed.
      */
-    @Test(dataProvider = "executors")
-    public void testClose5(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testClose5(ExecutorService executor) throws Exception {
         executor.close();
         executor.close(); // already closed
     }
@@ -290,8 +289,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test awaitTermination when not shutdown.
      */
-    @Test(dataProvider = "executors")
-    public void testAwaitTermination1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testAwaitTermination1(ExecutorService executor) throws Exception {
         assertFalse(executor.awaitTermination(100, TimeUnit.MILLISECONDS));
         executor.close();
         assertTrue(executor.awaitTermination(100, TimeUnit.MILLISECONDS));
@@ -300,8 +300,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test awaitTermination with task running.
      */
-    @Test(dataProvider = "executors")
-    public void testAwaitTermination2(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testAwaitTermination2(ExecutorService executor) throws Exception {
         Phaser barrier = new Phaser(2);
         Future<?> result = executor.submit(barrier::arriveAndAwaitAdvance);
         try {
@@ -317,8 +318,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test submit when the Executor is shutdown but not terminated.
      */
-    @Test(dataProvider = "executors")
-    public void testSubmitAfterShutdown(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testSubmitAfterShutdown(ExecutorService executor) throws Exception {
         Phaser barrier = new Phaser(2);
         try (executor) {
             // submit task to prevent executor from terminating
@@ -326,7 +328,7 @@ public class ThreadPerTaskExecutorTest {
             try {
                 executor.shutdown();
                 assertTrue(executor.isShutdown() && !executor.isTerminated());
-                expectThrows(RejectedExecutionException.class,
+                assertThrows(RejectedExecutionException.class,
                              () -> executor.submit(() -> {  }));
             } finally {
                 barrier.arriveAndAwaitAdvance();
@@ -337,24 +339,27 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test submit when the Executor is terminated.
      */
-    @Test(dataProvider = "executors")
-    public void testSubmitAfterTermination(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testSubmitAfterTermination(ExecutorService executor) throws Exception {
         executor.shutdown();
         assertTrue(executor.isShutdown() && executor.isTerminated());
-        expectThrows(RejectedExecutionException.class, () -> executor.submit(() -> {}));
+        assertThrows(RejectedExecutionException.class, () -> executor.submit(() -> {}));
     }
 
     /**
      * Test submit with null.
      */
-    @Test(dataProvider = "factories")
-    public void testSubmitNulls1(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testSubmitNulls1(ThreadFactory factory) {
         var executor = Executors.newThreadPerTaskExecutor(factory);
         assertThrows(NullPointerException.class, () -> executor.submit((Runnable) null));
     }
 
-    @Test(dataProvider = "factories")
-    public void testSubmitNulls2(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testSubmitNulls2(ThreadFactory factory) {
         var executor = Executors.newThreadPerTaskExecutor(factory);
         assertThrows(NullPointerException.class, () -> executor.submit((Callable<String>) null));
     }
@@ -362,8 +367,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny where all tasks complete normally.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAny1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAny1(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             Callable<String> task2 = () -> "bar";
@@ -376,8 +382,9 @@ public class ThreadPerTaskExecutorTest {
      * Test invokeAny where all tasks complete normally. The completion of the
      * first task should cancel remaining tasks.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAny2(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAny2(ExecutorService executor) throws Exception {
         try (executor) {
             AtomicBoolean task2Started = new AtomicBoolean();
             AtomicReference<Throwable> task2Exception = new AtomicReference<>();
@@ -408,8 +415,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny where all tasks complete with exception.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAny3(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAny3(ExecutorService executor) throws Exception {
         try (executor) {
             class FooException extends Exception { }
             Callable<String> task1 = () -> { throw new FooException(); };
@@ -428,8 +436,9 @@ public class ThreadPerTaskExecutorTest {
      * Test invokeAny where all tasks complete with exception. The completion
      * of the last task is delayed.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAny4(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAny4(ExecutorService executor) throws Exception {
         try (executor) {
             class FooException extends Exception { }
             Callable<String> task1 = () -> { throw new FooException(); };
@@ -450,8 +459,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny where some, not all, tasks complete normally.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAny5(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAny5(ExecutorService executor) throws Exception {
         try (executor) {
             class FooException extends Exception { }
             Callable<String> task1 = () -> "foo";
@@ -465,8 +475,9 @@ public class ThreadPerTaskExecutorTest {
      * Test invokeAny where some, not all, tasks complete normally. The
      * completion of the first task to complete normally is delayed.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAny6(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAny6(ExecutorService executor) throws Exception {
         try (executor) {
             class FooException extends Exception { }
             Callable<String> task1 = () -> {
@@ -482,8 +493,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test timed-invokeAny where all tasks complete normally before the timeout.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAnyWithTimeout1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAnyWithTimeout1(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             Callable<String> task2 = () -> "bar";
@@ -496,8 +508,9 @@ public class ThreadPerTaskExecutorTest {
      * Test timed-invokeAny where one task completes normally before the timeout.
      * The remaining tests should be cancelled.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAnyWithTimeout2(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAnyWithTimeout2(ExecutorService executor) throws Exception {
         try (executor) {
             AtomicBoolean task2Started = new AtomicBoolean();
             AtomicReference<Throwable> task2Exception = new AtomicReference<>();
@@ -528,8 +541,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test timed-invokeAny where timeout expires before any task completes.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAnyWithTimeout3(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAnyWithTimeout3(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> {
                 Thread.sleep(Duration.ofMinutes(1));
@@ -548,8 +562,9 @@ public class ThreadPerTaskExecutorTest {
      * Test invokeAny where timeout expires after some tasks have completed
      * with exception.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAnyWithTimeout4(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAnyWithTimeout4(ExecutorService executor) throws Exception {
         try (executor) {
             class FooException extends Exception { }
             Callable<String> task1 = () -> { throw new FooException(); };
@@ -565,8 +580,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny with interrupt status set.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAnyWithInterruptSet(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAnyWithInterruptSet(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             Callable<String> task2 = () -> "bar";
@@ -585,8 +601,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test interrupting a thread blocked in invokeAny.
      */
-    @Test(dataProvider = "executors")
-    public void testInterruptInvokeAny(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInterruptInvokeAny(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> {
                 Thread.sleep(Duration.ofMinutes(1));
@@ -611,8 +628,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny after ExecutorService has been shutdown.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAnyAfterShutdown(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAnyAfterShutdown(ExecutorService executor) throws Exception {
         executor.shutdown();
         Callable<String> task1 = () -> "foo";
         Callable<String> task2 = () -> "bar";
@@ -623,8 +641,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny with empty collection.
      */
-    @Test(dataProvider = "factories")
-    public void testInvokeAnyEmpty1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAnyEmpty1(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             assertThrows(IllegalArgumentException.class, () -> executor.invokeAny(Set.of()));
         }
@@ -633,8 +652,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test timed-invokeAny with empty collection.
      */
-    @Test(dataProvider = "factories")
-    public void testInvokeAnyEmpty2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAnyEmpty2(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             assertThrows(IllegalArgumentException.class,
                          () -> executor.invokeAny(Set.of(), 1, TimeUnit.MINUTES));
@@ -644,8 +664,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny with null.
      */
-    @Test(dataProvider = "factories")
-    public void testInvokeAnyNull1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAnyNull1(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             assertThrows(NullPointerException.class, () -> executor.invokeAny(null));
         }
@@ -654,8 +675,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAny with null element
      */
-    @Test(dataProvider = "factories")
-    public void testInvokeAnyNull2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAnyNull2(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             List<Callable<String>> list = new ArrayList<>();
             list.add(() -> "foo");
@@ -667,8 +689,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAll where all tasks complete normally.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAll1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAll1(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             Callable<String> task2 = () -> {
@@ -692,8 +715,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAll where all tasks complete with exception.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAll2(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAll2(ExecutorService executor) throws Exception {
         try (executor) {
             class FooException extends Exception { }
             class BarException extends Exception { }
@@ -711,9 +735,9 @@ public class ThreadPerTaskExecutorTest {
             assertFalse(notDone);
 
             // check results
-            Throwable e1 = expectThrows(ExecutionException.class, () -> list.get(0).get());
+            Throwable e1 = assertThrows(ExecutionException.class, () -> list.get(0).get());
             assertTrue(e1.getCause() instanceof FooException);
-            Throwable e2 = expectThrows(ExecutionException.class, () -> list.get(1).get());
+            Throwable e2 = assertThrows(ExecutionException.class, () -> list.get(1).get());
             assertTrue(e2.getCause() instanceof BarException);
         }
     }
@@ -721,8 +745,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAll where all tasks complete normally before the timeout expires.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAll3(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAll3(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             Callable<String> task2 = () -> {
@@ -746,8 +771,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAll where some tasks do not complete before the timeout expires.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAll4(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAll4(ExecutorService executor) throws Exception {
         try (executor) {
             AtomicReference<Exception> exc = new AtomicReference<>();
             Callable<String> task1 = () -> "foo";
@@ -784,8 +810,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAll with interrupt status set.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAllInterrupt1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllInterrupt1(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             Callable<String> task2 = () -> {
@@ -808,8 +835,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test timed-invokeAll with interrupt status set.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAllInterrupt3(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllInterrupt3(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             Callable<String> task2 = () -> {
@@ -832,8 +860,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test interrupt with thread blocked in invokeAll.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAllInterrupt4(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllInterrupt4(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             DelayedResult<String> task2 = new DelayedResult("bar", Duration.ofMinutes(1));
@@ -858,8 +887,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test interrupt with thread blocked in timed-invokeAll.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAllInterrupt6(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllInterrupt6(ExecutorService executor) throws Exception {
         try (executor) {
             Callable<String> task1 = () -> "foo";
             DelayedResult<String> task2 = new DelayedResult("bar", Duration.ofMinutes(1));
@@ -884,8 +914,9 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAll after ExecutorService has been shutdown.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAllAfterShutdown1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllAfterShutdown1(ExecutorService executor) throws Exception {
         executor.shutdown();
 
         Callable<String> task1 = () -> "foo";
@@ -894,8 +925,9 @@ public class ThreadPerTaskExecutorTest {
                      () -> executor.invokeAll(Set.of(task1, task2)));
     }
 
-    @Test(dataProvider = "executors")
-    public void testInvokeAllAfterShutdown2(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllAfterShutdown2(ExecutorService executor) throws Exception {
         executor.shutdown();
 
         Callable<String> task1 = () -> "foo";
@@ -907,31 +939,35 @@ public class ThreadPerTaskExecutorTest {
     /**
      * Test invokeAll with empty collection.
      */
-    @Test(dataProvider = "executors")
-    public void testInvokeAllEmpty1(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllEmpty1(ExecutorService executor) throws Exception {
         try (executor) {
             List<Future<Object>> list = executor.invokeAll(Set.of());
             assertTrue(list.size() == 0);
         }
     }
 
-    @Test(dataProvider = "executors")
-    public void testInvokeAllEmpty2(ExecutorService executor) throws Exception {
+    @ParameterizedTest
+    @MethodSource("executors")
+    void testInvokeAllEmpty2(ExecutorService executor) throws Exception {
         try (executor) {
             List<Future<Object>> list = executor.invokeAll(Set.of(), 1, TimeUnit.SECONDS);
             assertTrue(list.size() == 0);
         }
     }
 
-    @Test(dataProvider = "factories")
-    public void testInvokeAllNull1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAllNull1(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             assertThrows(NullPointerException.class, () -> executor.invokeAll(null));
         }
     }
 
-    @Test(dataProvider = "factories")
-    public void testInvokeAllNull2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAllNull2(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             List<Callable<String>> tasks = new ArrayList<>();
             tasks.add(() -> "foo");
@@ -940,16 +976,18 @@ public class ThreadPerTaskExecutorTest {
         }
     }
 
-    @Test(dataProvider = "factories")
-    public void testInvokeAllNull3(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAllNull3(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             assertThrows(NullPointerException.class,
                          () -> executor.invokeAll(null, 1, TimeUnit.SECONDS));
         }
     }
 
-    @Test(dataProvider = "factories")
-    public void testInvokeAllNull4(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAllNull4(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             Callable<String> task = () -> "foo";
             assertThrows(NullPointerException.class,
@@ -957,8 +995,9 @@ public class ThreadPerTaskExecutorTest {
         }
     }
 
-    @Test(dataProvider = "factories")
-    public void testInvokeAllNull5(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInvokeAllNull5(ThreadFactory factory) throws Exception {
         try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
             List<Callable<String>> tasks = new ArrayList<>();
             tasks.add(() -> "foo");
@@ -972,33 +1011,33 @@ public class ThreadPerTaskExecutorTest {
      * Test ThreadFactory that does not produce any threads
      */
     @Test
-    public void testNoThreads1() throws Exception {
+    void testNoThreads1() throws Exception {
         ExecutorService executor = Executors.newThreadPerTaskExecutor(task -> null);
         assertThrows(RejectedExecutionException.class, () -> executor.execute(() -> { }));
     }
 
     @Test
-    public void testNoThreads2() throws Exception {
+    void testNoThreads2() throws Exception {
         ExecutorService executor = Executors.newThreadPerTaskExecutor(task -> null);
         assertThrows(RejectedExecutionException.class, () -> executor.submit(() -> "foo"));
     }
 
     @Test
-    public void testNoThreads3() throws Exception {
+    void testNoThreads3() throws Exception {
         ExecutorService executor = Executors.newThreadPerTaskExecutor(task -> null);
         assertThrows(RejectedExecutionException.class,
                      () -> executor.invokeAll(List.of(() -> "foo")));
     }
 
     @Test
-    public void testNoThreads4() throws Exception {
+    void testNoThreads4() throws Exception {
         ExecutorService executor = Executors.newThreadPerTaskExecutor(task -> null);
         assertThrows(RejectedExecutionException.class,
                      () -> executor.invokeAny(List.of(() -> "foo")));
     }
 
     @Test
-    public void testNull() {
+    void testNull() {
         assertThrows(NullPointerException.class,
                      () -> Executors.newThreadPerTaskExecutor(null));
     }
diff --git a/test/jdk/jdk/incubator/concurrent/ScopedValue/ManyBindings.java b/test/jdk/jdk/incubator/concurrent/ScopedValue/ManyBindings.java
index f2b2c470ae7..1061c292824 100644
--- a/test/jdk/jdk/incubator/concurrent/ScopedValue/ManyBindings.java
+++ b/test/jdk/jdk/incubator/concurrent/ScopedValue/ManyBindings.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,7 +28,7 @@
  * @modules jdk.incubator.concurrent
  * @library /test/lib
  * @key randomness
- * @run testng ManyBindings
+ * @run junit ManyBindings
  */
 
 import jdk.incubator.concurrent.ScopedValue;
@@ -40,11 +40,10 @@ import java.util.Random;
 import jdk.test.lib.RandomFactory;
 import jdk.test.lib.thread.VThreadRunner;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-@Test
-public class ManyBindings {
+class ManyBindings {
     private static final Random RND = RandomFactory.getRandom();
 
     // number of scoped values to create
@@ -56,14 +55,16 @@ public class ManyBindings {
     /**
      * Stress test bindings on platform thread.
      */
-    public void testPlatformThread() {
+    @Test
+    void testPlatformThread() {
         test();
     }
 
     /**
      * Stress test bindings on virtual thread.
      */
-    public void testVirtualThread() throws Exception {
+    @Test
+    void testVirtualThread() throws Exception {
         VThreadRunner.run(() -> test());
     }
 
@@ -143,7 +144,7 @@ public class ManyBindings {
             if (value == null) {
                 assertFalse(key.isBound());
             } else {
-                assertEquals(key.get(), value);
+                assertEquals(value, key.get());
             }
         }
     }
@@ -157,7 +158,7 @@ public class ManyBindings {
             Integer value = array[index].value;
             if (value != null) {
                 ScopedValue<Integer> key = array[index].key;
-                assertEquals(key.get(), value);
+                assertEquals(value, key.get());
             }
         }
     }
diff --git a/test/jdk/jdk/incubator/concurrent/ScopedValue/ScopeValueAPI.java b/test/jdk/jdk/incubator/concurrent/ScopedValue/ScopeValueAPI.java
index 690f974a539..ca060ae96ed 100644
--- a/test/jdk/jdk/incubator/concurrent/ScopedValue/ScopeValueAPI.java
+++ b/test/jdk/jdk/incubator/concurrent/ScopedValue/ScopeValueAPI.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,7 +26,7 @@
  * @summary Test ScopedValue API
  * @enablePreview
  * @modules jdk.incubator.concurrent
- * @run testng ScopeValueAPI
+ * @run junit ScopeValueAPI
  */
 
 import jdk.incubator.concurrent.ScopedValue;
@@ -35,27 +35,25 @@ import java.util.concurrent.Callable;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ThreadFactory;
+import java.util.stream.Stream;
 
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
 
-@Test
-public class ScopeValueAPI {
+class ScopeValueAPI {
 
-    @DataProvider
-    public Object[][] factories() {
-        return new Object[][] {
-                { Thread.ofPlatform().factory() },
-                { Thread.ofVirtual().factory() },
-        };
+    private static Stream<ThreadFactory> factories() {
+        return Stream.of(Thread.ofPlatform().factory(), Thread.ofVirtual().factory());
     }
 
     /**
      * Test that the run method is invoked.
      */
-    @Test(dataProvider = "factories")
-    public void testRun(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testRun(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             class Box { static boolean executed; }
             ScopedValue<String> name = ScopedValue.newInstance();
@@ -67,8 +65,9 @@ public class ScopeValueAPI {
     /**
      * Test the run method throwing an exception.
      */
-    @Test(dataProvider = "factories")
-    public void testRunThrows(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testRunThrows(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             class FooException extends RuntimeException {  }
             ScopedValue<String> name = ScopedValue.newInstance();
@@ -81,20 +80,22 @@ public class ScopeValueAPI {
     /**
      * Test that the call method is invoked.
      */
-    @Test(dataProvider = "factories")
-    public void testCall(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCall(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name = ScopedValue.newInstance();
             String result = ScopedValue.where(name, "duke", name::get);
-            assertEquals(result, "duke");
+            assertEquals("duke", result);
         });
     }
 
     /**
      * Test the call method throwing an exception.
      */
-    @Test(dataProvider = "factories")
-    public void testCallThrows(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCallThrows(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             class FooException extends RuntimeException {  }
             ScopedValue<String> name = ScopedValue.newInstance();
@@ -107,8 +108,9 @@ public class ScopeValueAPI {
     /**
      * Test get method.
      */
-    @Test(dataProvider = "factories")
-    public void testGet(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testGet(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name1 = ScopedValue.newInstance();
             ScopedValue<String> name2 = ScopedValue.newInstance();
@@ -117,7 +119,7 @@ public class ScopeValueAPI {
 
             // run
             ScopedValue.where(name1, "duke", () -> {
-                assertEquals(name1.get(), "duke");
+                assertEquals("duke", name1.get());
                 assertThrows(NoSuchElementException.class, name2::get);
 
             });
@@ -126,7 +128,7 @@ public class ScopeValueAPI {
 
             // call
             ScopedValue.where(name1, "duke", () -> {
-                assertEquals(name1.get(), "duke");
+                assertEquals("duke", name1.get());
                 assertThrows(NoSuchElementException.class, name2::get);
                 return null;
             });
@@ -138,8 +140,9 @@ public class ScopeValueAPI {
     /**
      * Test isBound method.
      */
-    @Test(dataProvider = "factories")
-    public void testIsBound(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testIsBound(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name1 = ScopedValue.newInstance();
             ScopedValue<String> name2 = ScopedValue.newInstance();
@@ -168,23 +171,24 @@ public class ScopeValueAPI {
     /**
      * Test orElse method.
      */
-    @Test(dataProvider = "factories")
-    public void testOrElse(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testOrElse(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name = ScopedValue.newInstance();
-            assertTrue(name.orElse(null) == null);
-            assertEquals(name.orElse("default"), "default");
+            assertNull(name.orElse(null));
+            assertEquals("default", name.orElse("default"));
 
             // run
             ScopedValue.where(name, "duke", () -> {
-                assertEquals(name.orElse(null), "duke");
-                assertEquals(name.orElse("default"), "duke");
+                assertEquals("duke", name.orElse(null));
+                assertEquals("duke", name.orElse("default"));
             });
 
             // call
             ScopedValue.where(name, "duke", () -> {
-                assertEquals(name.orElse(null), "duke");
-                assertEquals(name.orElse("default"), "duke");
+                assertEquals("duke", name.orElse(null));
+                assertEquals("duke", name.orElse("default"));
                 return null;
             });
         });
@@ -193,8 +197,9 @@ public class ScopeValueAPI {
     /**
      * Test orElseThrow method.
      */
-    @Test(dataProvider = "factories")
-    public void testOrElseThrow(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testOrElseThrow(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             class FooException extends RuntimeException { }
             ScopedValue<String> name = ScopedValue.newInstance();
@@ -202,12 +207,12 @@ public class ScopeValueAPI {
 
             // run
             ScopedValue.where(name, "duke", () -> {
-                assertEquals(name.orElseThrow(FooException::new), "duke");
+                assertEquals("duke", name.orElseThrow(FooException::new));
             });
 
             // call
             ScopedValue.where(name, "duke", () -> {
-                assertEquals(name.orElseThrow(FooException::new), "duke");
+                assertEquals("duke", name.orElseThrow(FooException::new));
                 return null;
             });
         });
@@ -216,8 +221,9 @@ public class ScopeValueAPI {
     /**
      * Test two bindings.
      */
-    @Test(dataProvider = "factories")
-    public void testTwoBindings(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testTwoBindings(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name = ScopedValue.newInstance();
             ScopedValue<Integer> age = ScopedValue.newInstance();
@@ -226,8 +232,8 @@ public class ScopeValueAPI {
             ScopedValue.where(name, "duke").where(age, 100).run(() -> {
                 assertTrue(name.isBound());
                 assertTrue(age.isBound());
-                assertEquals(name.get(), "duke");
-                assertEquals((int) age.get(), 100);
+                assertEquals("duke", name.get());
+                assertEquals(100, (int) age.get());
             });
             assertFalse(name.isBound());
             assertFalse(age.isBound());
@@ -236,8 +242,8 @@ public class ScopeValueAPI {
             ScopedValue.where(name, "duke").where(age, 100).call(() -> {
                 assertTrue(name.isBound());
                 assertTrue(age.isBound());
-                assertEquals(name.get(), "duke");
-                assertEquals((int) age.get(), 100);
+                assertEquals("duke", name.get());
+                assertEquals(100, (int) age.get());
                 return null;
             });
             assertFalse(name.isBound());
@@ -249,39 +255,40 @@ public class ScopeValueAPI {
     /**
      * Test rebinding.
      */
-    @Test(dataProvider = "factories")
-    public void testRebinding(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testRebinding(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name = ScopedValue.newInstance();
 
             // run
             ScopedValue.where(name, "duke", () -> {
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
 
                 ScopedValue.where(name, "duchess", () -> {
                     assertTrue(name.isBound());
-                    assertTrue("duchess".equals(name.get()));
+                    assertEquals("duchess", name.get());
                 });
 
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
             });
             assertFalse(name.isBound());
 
             // call
             ScopedValue.where(name, "duke", () -> {
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
 
                 ScopedValue.where(name, "duchess", () -> {
                     assertTrue(name.isBound());
-                    assertTrue("duchess".equals(name.get()));
+                    assertEquals("duchess", name.get());
                     return null;
                 });
 
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
                 return null;
             });
             assertFalse(name.isBound());
@@ -291,15 +298,16 @@ public class ScopeValueAPI {
     /**
      * Test rebinding from null vaue to another value.
      */
-    @Test(dataProvider = "factories")
-    public void testRebindingFromNull(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testRebindingFromNull(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name = ScopedValue.newInstance();
 
             // run
             ScopedValue.where(name, null, () -> {
                 assertTrue(name.isBound());
-                assertEquals(name.get(), null);
+                assertNull(name.get());
 
                 ScopedValue.where(name, "duchess", () -> {
                     assertTrue(name.isBound());
@@ -307,14 +315,14 @@ public class ScopeValueAPI {
                 });
 
                 assertTrue(name.isBound());
-                assertTrue(name.get() == null);
+                assertNull(name.get());
             });
             assertFalse(name.isBound());
 
             // call
             ScopedValue.where(name, null, () -> {
                 assertTrue(name.isBound());
-                assertEquals(name.get(), null);
+                assertNull(name.get());
 
                 ScopedValue.where(name, "duchess", () -> {
                     assertTrue(name.isBound());
@@ -323,7 +331,7 @@ public class ScopeValueAPI {
                 });
 
                 assertTrue(name.isBound());
-                assertTrue(name.get() == null);
+                assertNull(name.get());
                 return null;
             });
             assertFalse(name.isBound());
@@ -333,39 +341,40 @@ public class ScopeValueAPI {
     /**
      * Test rebinding to null value.
      */
-    @Test(dataProvider = "factories")
-    public void testRebindingToNull(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testRebindingToNull(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name = ScopedValue.newInstance();
 
             // run
             ScopedValue.where(name, "duke", () -> {
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
 
                 ScopedValue.where(name, null, () -> {
                     assertTrue(name.isBound());
-                    assertTrue(name.get() == null);
+                    assertNull(name.get());
                 });
 
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
             });
             assertFalse(name.isBound());
 
             // call
             ScopedValue.where(name, "duke", () -> {
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
 
                 ScopedValue.where(name, null, () -> {
                     assertTrue(name.isBound());
-                    assertTrue(name.get() == null);
+                    assertNull(name.get());
                     return null;
                 });
 
                 assertTrue(name.isBound());
-                assertEquals(name.get(), "duke");
+                assertEquals("duke", name.get());
                 return null;
             });
             assertFalse(name.isBound());
@@ -375,28 +384,30 @@ public class ScopeValueAPI {
     /**
      * Test Carrier.get.
      */
-    @Test(dataProvider = "factories")
-    public void testCarrierGet(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCarrierGet(ThreadFactory factory) throws Exception {
         test(factory, () -> {
             ScopedValue<String> name = ScopedValue.newInstance();
             ScopedValue<Integer> age = ScopedValue.newInstance();
 
             // one scoped value
             var carrier1 = ScopedValue.where(name, "duke");
-            assertEquals(carrier1.get(name), "duke");
+            assertEquals("duke", carrier1.get(name));
             assertThrows(NoSuchElementException.class, () -> carrier1.get(age));
 
             // two scoped values
             var carrier2 = carrier1.where(age, 20);
-            assertEquals(carrier2.get(name), "duke");
-            assertEquals((int) carrier2.get(age), 20);
+            assertEquals("duke", carrier2.get(name));
+            assertEquals(20, (int) carrier2.get(age));
         });
     }
 
     /**
      * Test NullPointerException.
      */
-    public void testNullPointerException() {
+    @Test
+    void testNullPointerException() {
         ScopedValue<String> name = ScopedValue.newInstance();
 
         assertThrows(NullPointerException.class, () -> ScopedValue.where(null, "value"));
diff --git a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/PreviewFeaturesNotEnabled.java b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/PreviewFeaturesNotEnabled.java
index c02d74d1ab9..65cb6c26d2f 100644
--- a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/PreviewFeaturesNotEnabled.java
+++ b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/PreviewFeaturesNotEnabled.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,19 +26,19 @@
  * @bug 8284199
  * @summary Test StructuredTaskScope without --enable-preview
  * @modules jdk.incubator.concurrent
- * @run testng/othervm PreviewFeaturesNotEnabled
+ * @run junit/othervm PreviewFeaturesNotEnabled
  */
 
 import jdk.incubator.concurrent.StructuredTaskScope;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class PreviewFeaturesNotEnabled {
+class PreviewFeaturesNotEnabled {
     /**
      * One-arg constructor needs --enable-preview.
      */
     @Test
-    public void testUnsupportedOperationException() {
+    void testUnsupportedOperationException() {
         assertThrows(UnsupportedOperationException.class, StructuredTaskScope::new);
     }
 
@@ -46,7 +46,7 @@ public class PreviewFeaturesNotEnabled {
      * Two-arg constructor does not need --enable-preview.
      */
     @Test
-    public void testNoUnsupportedOperationException() {
+    void testNoUnsupportedOperationException() {
         try (var scope = new StructuredTaskScope<Object>(null, Thread::new)) {
         }
     }
diff --git a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredTaskScopeTest.java b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredTaskScopeTest.java
index 7d85e456720..ba6a22b83d1 100644
--- a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredTaskScopeTest.java
+++ b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredTaskScopeTest.java
@@ -27,14 +27,14 @@
  * @summary Basic tests for StructuredTaskScope
  * @enablePreview
  * @modules jdk.incubator.concurrent
- * @run testng/othervm -DthreadFactory=platform StructuredTaskScopeTest
+ * @run junit/othervm -DthreadFactory=platform StructuredTaskScopeTest
  */
 
 /*
  * @test id=virtual
  * @enablePreview
  * @modules jdk.incubator.concurrent
- * @run testng/othervm -DthreadFactory=virtual StructuredTaskScopeTest
+ * @run junit/othervm -DthreadFactory=virtual StructuredTaskScopeTest
  */
 
 import jdk.incubator.concurrent.StructuredTaskScope;
@@ -65,24 +65,21 @@ import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
-import org.testng.annotations.AfterClass;
-import org.testng.annotations.BeforeClass;
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
 
-public class StructuredTaskScopeTest {
-    private ScheduledExecutorService scheduler;
-    private Object[][] threadFactories;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
 
-    @BeforeClass
-    public void setUp() throws Exception {
-        ThreadFactory factory = (task) -> {
-            Thread thread = new Thread(task);
-            thread.setDaemon(true);
-            return thread;
-        };
-        this.scheduler = Executors.newSingleThreadScheduledExecutor(factory);
+class StructuredTaskScopeTest {
+    private static ScheduledExecutorService scheduler;
+    private static List<ThreadFactory> threadFactories;
+
+    @BeforeAll
+    static void setup() throws Exception {
+        scheduler = Executors.newSingleThreadScheduledExecutor();
 
         // thread factories
         String value = System.getProperty("threadFactory");
@@ -92,29 +89,24 @@ public class StructuredTaskScopeTest {
         if (value == null || value.equals("virtual"))
             list.add(Thread.ofVirtual().factory());
         assertTrue(list.size() > 0, "No thread factories for tests");
-        this.threadFactories = list.stream()
-                .map(f -> new Object[] { f })
-                .toArray(Object[][]::new);
+        threadFactories = list;
     }
 
-    @AfterClass
-    public void tearDown() {
+    @AfterAll
+    static void shutdown() {
         scheduler.shutdown();
     }
 
-    /**
-     * A provider of ThreadFactory objects for tests.
-     */
-    @DataProvider
-    public Object[][] factories() {
-        return threadFactories;
+    private static Stream<ThreadFactory> factories() {
+        return threadFactories.stream();
     }
 
     /**
      * Test that each fork creates a thread.
      */
-    @Test(dataProvider = "factories")
-    public void testFork1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testFork1(ThreadFactory factory) throws Exception {
         AtomicInteger count = new AtomicInteger();
         try (var scope = new StructuredTaskScope(null, factory)) {
             for (int i = 0; i < 100; i++) {
@@ -128,8 +120,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test that fork uses the specified thread factory.
      */
-    @Test(dataProvider = "factories")
-    public void testFork2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testFork2(ThreadFactory factory) throws Exception {
         AtomicInteger count = new AtomicInteger();
         ThreadFactory countingFactory = task -> {
             count.incrementAndGet();
@@ -147,8 +140,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test fork is confined to threads in the scope "tree".
      */
-    @Test(dataProvider = "factories")
-    public void testForkConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testForkConfined(ThreadFactory factory) throws Exception {
         try (var scope1 = new StructuredTaskScope();
              var scope2 = new StructuredTaskScope()) {
 
@@ -157,7 +151,7 @@ public class StructuredTaskScopeTest {
                 scope2.fork(() -> null).get();
                 return null;
             });
-            Throwable ex = expectThrows(ExecutionException.class, future1::get);
+            Throwable ex = assertThrows(ExecutionException.class, future1::get);
             assertTrue(ex.getCause() instanceof WrongThreadException);
 
             // thread in scope2 can fork thread in scope1
@@ -166,7 +160,7 @@ public class StructuredTaskScopeTest {
                 return null;
             });
             future2.get();
-            assertTrue(future2.resultNow() == null);
+            assertNull(future2.resultNow());
 
             // random thread cannot fork
             try (var pool = Executors.newCachedThreadPool(factory)) {
@@ -174,7 +168,7 @@ public class StructuredTaskScopeTest {
                     scope1.fork(() -> null);
                     return null;
                 });
-                ex = expectThrows(ExecutionException.class, future::get);
+                ex = assertThrows(ExecutionException.class, future::get);
                 assertTrue(ex.getCause() instanceof WrongThreadException);
             }
 
@@ -186,8 +180,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test fork when scope is shutdown.
      */
-    @Test(dataProvider = "factories")
-    public void testForkAfterShutdown(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testForkAfterShutdown(ThreadFactory factory) throws Exception {
         AtomicInteger count = new AtomicInteger();
         try (var scope = new StructuredTaskScope(null, factory)) {
             scope.shutdown();
@@ -204,8 +199,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test fork when scope is closed.
      */
-    @Test(dataProvider = "factories")
-    public void testForkAfterClose(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testForkAfterClose(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             scope.join();
             scope.close();
@@ -217,7 +213,7 @@ public class StructuredTaskScopeTest {
      * Test fork when the thread factory rejects creating a thread.
      */
     @Test
-    public void testForkReject() throws Exception {
+    void testForkReject() throws Exception {
         ThreadFactory factory = task -> null;
         try (var scope = new StructuredTaskScope(null, factory)) {
             assertThrows(RejectedExecutionException.class, () -> scope.fork(() -> null));
@@ -255,8 +251,9 @@ public class StructuredTaskScopeTest {
      * Test that handleComplete method is invoked for tasks that complete normally
      * and abnormally.
      */
-    @Test(dataProvider = "factories")
-    public void testHandleComplete1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testHandleComplete1(ThreadFactory factory) throws Exception {
         try (var scope = new CollectAll(factory)) {
 
             // completes normally
@@ -275,17 +272,17 @@ public class StructuredTaskScopeTest {
             scope.join();
 
             Set<Future<String>> futures = scope.futuresAsSet();
-            assertEquals(futures, Set.of(future1, future2, future3));
+            assertEquals(Set.of(future1, future2, future3), futures);
         }
     }
 
     /**
      * Test that the handeComplete method is not invoked after the scope has been shutdown.
      */
-    @Test(dataProvider = "factories")
-    public void testHandleComplete2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testHandleComplete2(ThreadFactory factory) throws Exception {
         try (var scope = new CollectAll(factory)) {
-
             var latch = new CountDownLatch(1);
 
             // start task that does not respond to interrupt
@@ -322,7 +319,7 @@ public class StructuredTaskScopeTest {
      * Test join with no threads.
      */
     @Test
-    public void testJoinWithNoThreads() throws Exception {
+    void testJoinWithNoThreads() throws Exception {
         try (var scope = new StructuredTaskScope()) {
             scope.join();
         }
@@ -331,30 +328,32 @@ public class StructuredTaskScopeTest {
     /**
      * Test join with threads running.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinWithThreads(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinWithThreads(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             Future<String> future = scope.fork(() -> {
                 Thread.sleep(Duration.ofMillis(50));
                 return "foo";
             });
             scope.join();
-            assertEquals(future.resultNow(), "foo");
+            assertEquals("foo", future.resultNow());
         }
     }
 
     /**
      * Test join is owner confined.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinConfined(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope()) {
             // attempt to join on thread in scope
             Future<Void> future1 = scope.fork(() -> {
                 scope.join();
                 return null;
             });
-            Throwable ex = expectThrows(ExecutionException.class, future1::get);
+            Throwable ex = assertThrows(ExecutionException.class, future1::get);
             assertTrue(ex.getCause() instanceof WrongThreadException);
 
             // random thread cannot join
@@ -363,7 +362,7 @@ public class StructuredTaskScopeTest {
                     scope.join();
                     return null;
                 });
-                ex = expectThrows(ExecutionException.class, future2::get);
+                ex = assertThrows(ExecutionException.class, future2::get);
                 assertTrue(ex.getCause() instanceof WrongThreadException);
             }
 
@@ -374,11 +373,14 @@ public class StructuredTaskScopeTest {
     /**
      * Test join with interrupt status set.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptJoin1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptJoin1(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
+            var latch = new CountDownLatch(1);
+
             Future<String> future = scope.fork(() -> {
-                Thread.sleep(Duration.ofMillis(100));
+                latch.await();
                 return "foo";
             });
 
@@ -389,22 +391,28 @@ public class StructuredTaskScopeTest {
                 fail("join did not throw");
             } catch (InterruptedException expected) {
                 assertFalse(Thread.interrupted());   // interrupt status should be clear
+            } finally {
+                // let task continue
+                latch.countDown();
             }
 
             // join should complete
             scope.join();
-            assertEquals(future.resultNow(), "foo");
+            assertEquals("foo", future.resultNow());
         }
     }
 
     /**
      * Test interrupt of thread blocked in join.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptJoin2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptJoin2(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
+            var latch = new CountDownLatch(1);
+
             Future<String> future = scope.fork(() -> {
-                Thread.sleep(Duration.ofSeconds(3));
+                latch.await();
                 return "foo";
             });
 
@@ -415,19 +423,23 @@ public class StructuredTaskScopeTest {
                 fail("join did not throw");
             } catch (InterruptedException expected) {
                 assertFalse(Thread.interrupted());   // interrupt status should be clear
+            } finally {
+                // let task continue
+                latch.countDown();
             }
 
             // join should complete
             scope.join();
-            assertEquals(future.resultNow(), "foo");
+            assertEquals("foo", future.resultNow());
         }
     }
 
     /**
      * Test join when scope is already shutdown.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinWithShutdown1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinWithShutdown1(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             Future<String> future = scope.fork(() -> {
                 Thread.sleep(Duration.ofDays(1));
@@ -444,8 +456,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test shutdown when owner is blocked in join.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinWithShutdown2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinWithShutdown2(ThreadFactory factory) throws Exception {
         class MyScope<T> extends StructuredTaskScope<T> {
             MyScope(ThreadFactory factory) {
                 super(null, factory);
@@ -479,7 +492,7 @@ public class StructuredTaskScopeTest {
      * Test join after scope is shutdown.
      */
     @Test
-    public void testJoinAfterShutdown() throws Exception {
+    void testJoinAfterShutdown() throws Exception {
         try (var scope = new StructuredTaskScope()) {
             scope.shutdown();
             scope.join();
@@ -490,7 +503,7 @@ public class StructuredTaskScopeTest {
      * Test join after scope is closed.
      */
     @Test
-    public void testJoinAfterClose() throws Exception {
+    void testJoinAfterClose() throws Exception {
         try (var scope = new StructuredTaskScope()) {
             scope.join();
             scope.close();
@@ -502,8 +515,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test joinUntil, threads finish before deadline expires.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinUntil1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinUntil1(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             Future<String> future = scope.fork(() -> {
                 try {
@@ -514,7 +528,8 @@ public class StructuredTaskScopeTest {
 
             long startMillis = millisTime();
             scope.joinUntil(Instant.now().plusSeconds(30));
-            assertTrue(future.isDone() && future.resultNow() == null);
+            assertTrue(future.isDone());
+            assertNull(future.resultNow());
             expectDuration(startMillis, /*min*/1900, /*max*/20_000);
         }
     }
@@ -522,8 +537,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test joinUntil, deadline expires before threads finish.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinUntil2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinUntil2(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             Future<String> future = scope.fork(() -> {
                 try {
@@ -545,8 +561,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test joinUntil many times.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinUntil3(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinUntil3(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             Future<String> future = scope.fork(() -> {
                 try {
@@ -573,8 +590,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test joinUntil with a deadline that has already expired.
      */
-    @Test(dataProvider = "factories")
-    public void testJoinUntil4(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testJoinUntil4(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             Future<String> future = scope.fork(() -> {
                 try {
@@ -610,37 +628,46 @@ public class StructuredTaskScopeTest {
     /**
      * Test joinUntil with interrupt status set.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptJoinUntil1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptJoinUntil1(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
+            var latch = new CountDownLatch(1);
+
             Future<String> future = scope.fork(() -> {
-                Thread.sleep(Duration.ofSeconds(2));
+                latch.await();
                 return "foo";
             });
 
             // joinUntil should throw
             Thread.currentThread().interrupt();
             try {
-                scope.joinUntil(Instant.now().plusSeconds(10));
+                scope.joinUntil(Instant.now().plusSeconds(30));
                 fail("joinUntil did not throw");
             } catch (InterruptedException expected) {
                 assertFalse(Thread.interrupted());   // interrupt status should be clear
+            } finally {
+                // let task continue
+                latch.countDown();
             }
 
             // join should complete
             scope.join();
-            assertEquals(future.resultNow(), "foo");
+            assertEquals("foo", future.resultNow());
         }
     }
 
     /**
      * Test interrupt of thread blocked in joinUntil.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptJoinUntil2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptJoinUntil2(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
+            var latch = new CountDownLatch(1);
+
             Future<String> future = scope.fork(() -> {
-                Thread.sleep(Duration.ofSeconds(3));
+                latch.await();
                 return "foo";
             });
 
@@ -651,18 +678,22 @@ public class StructuredTaskScopeTest {
                 fail("joinUntil did not throw");
             } catch (InterruptedException expected) {
                 assertFalse(Thread.interrupted());   // interrupt status should be clear
+            } finally {
+                // let task continue
+                latch.countDown();
             }
 
             // join should complete
             scope.join();
-            assertEquals(future.resultNow(), "foo");
+            assertEquals("foo", future.resultNow());
         }
     }
 
     /**
      * Test shutdown after scope is closed.
      */
-    public void testShutdownAfterClose() throws Exception {
+    @Test
+    void testShutdownAfterClose() throws Exception {
         try (var scope = new StructuredTaskScope()) {
             scope.join();
             scope.close();
@@ -673,8 +704,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test shutdown is confined to threads in the scope "tree".
      */
-    @Test(dataProvider = "factories")
-    public void testShutdownConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testShutdownConfined(ThreadFactory factory) throws Exception {
         try (var scope1 = new StructuredTaskScope();
              var scope2 = new StructuredTaskScope()) {
 
@@ -684,7 +716,7 @@ public class StructuredTaskScopeTest {
                     scope1.shutdown();
                     return null;
                 });
-                Throwable ex = expectThrows(ExecutionException.class, future::get);
+                Throwable ex = assertThrows(ExecutionException.class, future::get);
                 assertTrue(ex.getCause() instanceof WrongThreadException);
             }
 
@@ -693,7 +725,7 @@ public class StructuredTaskScopeTest {
                 scope2.shutdown();
                 return null;
             });
-            Throwable ex = expectThrows(ExecutionException.class, future1::get);
+            Throwable ex = assertThrows(ExecutionException.class, future1::get);
             assertTrue(ex.getCause() instanceof WrongThreadException);
 
             // thread in scope2 can shutdown scope1
@@ -702,7 +734,7 @@ public class StructuredTaskScopeTest {
                 return null;
             });
             future2.get();
-            assertTrue(future2.resultNow() == null);
+            assertNull(future2.resultNow());
 
             scope2.join();
             scope1.join();
@@ -712,7 +744,8 @@ public class StructuredTaskScopeTest {
     /**
      * Test close without join, no threads forked.
      */
-    public void testCloseWithoutJoin1() {
+    @Test
+    void testCloseWithoutJoin1() {
         try (var scope = new StructuredTaskScope()) {
             // do nothing
         }
@@ -721,8 +754,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test close without join, threads forked.
      */
-    @Test(dataProvider = "factories")
-    public void testCloseWithoutJoin2(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCloseWithoutJoin2(ThreadFactory factory) {
         try (var scope = new StructuredTaskScope(null, factory)) {
             Future<String> future = scope.fork(() -> {
                 Thread.sleep(Duration.ofDays(1));
@@ -736,8 +770,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test close with threads forked after join.
      */
-    @Test(dataProvider = "factories")
-    public void testCloseWithoutJoin3(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCloseWithoutJoin3(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             scope.fork(() -> "foo");
             scope.join();
@@ -754,15 +789,16 @@ public class StructuredTaskScopeTest {
     /**
      * Test close is owner confined.
      */
-    @Test(dataProvider = "factories")
-    public void testCloseConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCloseConfined(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope()) {
             // attempt to close on thread in scope
             Future<Void> future1 = scope.fork(() -> {
                 scope.close();
                 return null;
             });
-            Throwable ex = expectThrows(ExecutionException.class, future1::get);
+            Throwable ex = assertThrows(ExecutionException.class, future1::get);
             assertTrue(ex.getCause() instanceof WrongThreadException);
 
             // random thread cannot close scope
@@ -771,7 +807,7 @@ public class StructuredTaskScopeTest {
                     scope.close();
                     return null;
                 });
-                ex = expectThrows(ExecutionException.class, future2::get);
+                ex = assertThrows(ExecutionException.class, future2::get);
                 assertTrue(ex.getCause() instanceof WrongThreadException);
             }
 
@@ -782,8 +818,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test close with interrupt status set.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptClose1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptClose1(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             var latch = new CountDownLatch(1);
 
@@ -818,8 +855,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test interrupting thread waiting in close.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptClose2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptClose2(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
             var latch = new CountDownLatch(1);
 
@@ -854,7 +892,7 @@ public class StructuredTaskScopeTest {
      * nested scope.
      */
     @Test
-    public void testStructureViolation1() throws Exception {
+    void testStructureViolation1() throws Exception {
         try (var scope1 = new StructuredTaskScope()) {
             try (var scope2 = new StructuredTaskScope()) {
 
@@ -881,8 +919,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test Future::get, task completes normally.
      */
-    @Test(dataProvider = "factories")
-    public void testFuture1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testFuture1(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
 
             Future<String> future = scope.fork(() -> {
@@ -890,9 +929,9 @@ public class StructuredTaskScopeTest {
                 return "foo";
             });
 
-            assertEquals(future.get(), "foo");
+            assertEquals("foo", future.get());
             assertTrue(future.state() == Future.State.SUCCESS);
-            assertEquals(future.resultNow(), "foo");
+            assertEquals("foo", future.resultNow());
 
             scope.join();
         }
@@ -901,8 +940,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test Future::get, task completes with exception.
      */
-    @Test(dataProvider = "factories")
-    public void testFuture2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testFuture2(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
 
             Future<String> future = scope.fork(() -> {
@@ -910,7 +950,7 @@ public class StructuredTaskScopeTest {
                 throw new FooException();
             });
 
-            Throwable ex = expectThrows(ExecutionException.class, future::get);
+            Throwable ex = assertThrows(ExecutionException.class, future::get);
             assertTrue(ex.getCause() instanceof FooException);
             assertTrue(future.state() == Future.State.FAILED);
             assertTrue(future.exceptionNow() instanceof FooException);
@@ -922,8 +962,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test Future::get, task is cancelled.
      */
-    @Test(dataProvider = "factories")
-    public void testFuture3(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testFuture3(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
 
             Future<String> future = scope.fork(() -> {
@@ -948,8 +989,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test scope shutdown with a thread blocked in Future::get.
      */
-    @Test(dataProvider = "factories")
-    public void testFutureWithShutdown(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testFutureWithShutdown(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope(null, factory)) {
 
             // long running task
@@ -985,8 +1027,9 @@ public class StructuredTaskScopeTest {
     /**
      * Test Future::cancel throws if invoked by a thread that is not in the tree.
      */
-    @Test(dataProvider = "factories")
-    public void testFutureCancelConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testFutureCancelConfined(ThreadFactory factory) throws Exception {
         try (var scope = new StructuredTaskScope()) {
             Future<String> future1 = scope.fork(() -> {
                 Thread.sleep(Duration.ofDays(1));
@@ -999,7 +1042,7 @@ public class StructuredTaskScopeTest {
                     future1.cancel(true);
                     return null;
                 });
-                Throwable ex = expectThrows(ExecutionException.class, future2::get);
+                Throwable ex = assertThrows(ExecutionException.class, future2::get);
                 assertTrue(ex.getCause() instanceof WrongThreadException);
             } finally {
                 future1.cancel(true);
@@ -1012,7 +1055,7 @@ public class StructuredTaskScopeTest {
      * Test StructuredTaskScope::toString includes the scope name.
      */
     @Test
-    public void testToString() throws Exception {
+    void testToString() throws Exception {
         ThreadFactory factory = Thread.ofVirtual().factory();
         try (var scope = new StructuredTaskScope("xxx", factory)) {
             // open
@@ -1033,7 +1076,7 @@ public class StructuredTaskScopeTest {
      * Test for NullPointerException.
      */
     @Test
-    public void testNulls() throws Exception {
+    void testNulls() throws Exception {
         assertThrows(NullPointerException.class, () -> new StructuredTaskScope("", null));
         try (var scope = new StructuredTaskScope()) {
             assertThrows(NullPointerException.class, () -> scope.fork(null));
@@ -1059,7 +1102,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnSuccess with no completed tasks.
      */
     @Test
-    public void testShutdownOnSuccess1() throws Exception {
+    void testShutdownOnSuccess1() throws Exception {
         try (var scope = new ShutdownOnSuccess<String>()) {
             assertThrows(IllegalStateException.class, () -> scope.result());
             assertThrows(IllegalStateException.class, () -> scope.result(e -> null));
@@ -1070,7 +1113,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnSuccess with tasks that completed normally.
      */
     @Test
-    public void testShutdownOnSuccess2() throws Exception {
+    void testShutdownOnSuccess2() throws Exception {
         try (var scope = new ShutdownOnSuccess<String>()) {
 
             // two tasks complete normally
@@ -1079,8 +1122,8 @@ public class StructuredTaskScopeTest {
             scope.fork(() -> "bar");
             scope.join();
 
-            assertEquals(scope.result(), "foo");
-            assertEquals(scope.result(e -> null), "foo");
+            assertEquals("foo", scope.result());
+            assertEquals("foo", scope.result(e -> null));
         }
     }
 
@@ -1088,7 +1131,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnSuccess with tasks that completed normally and abnormally.
      */
     @Test
-    public void testShutdownOnSuccess3() throws Exception {
+    void testShutdownOnSuccess3() throws Exception {
         try (var scope = new ShutdownOnSuccess<String>()) {
 
             // one task completes normally, the other with an exception
@@ -1096,8 +1139,8 @@ public class StructuredTaskScopeTest {
             scope.fork(() -> { throw new ArithmeticException(); });
             scope.join();
 
-            assertEquals(scope.result(), "foo");
-            assertEquals(scope.result(e -> null), "foo");
+            assertEquals("foo", scope.result());
+            assertEquals("foo", scope.result(e -> null));
         }
     }
 
@@ -1105,17 +1148,17 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnSuccess with a task that completed with an exception.
      */
     @Test
-    public void testShutdownOnSuccess4() throws Exception {
+    void testShutdownOnSuccess4() throws Exception {
         try (var scope = new ShutdownOnSuccess<String>()) {
 
             // tasks completes with exception
             scope.fork(() -> { throw new ArithmeticException(); });
             scope.join();
 
-            Throwable ex = expectThrows(ExecutionException.class, () -> scope.result());
+            Throwable ex = assertThrows(ExecutionException.class, () -> scope.result());
             assertTrue(ex.getCause() instanceof  ArithmeticException);
 
-            ex = expectThrows(FooException.class, () -> scope.result(e -> new FooException(e)));
+            ex = assertThrows(FooException.class, () -> scope.result(e -> new FooException(e)));
             assertTrue(ex.getCause() instanceof  ArithmeticException);
         }
     }
@@ -1124,7 +1167,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnSuccess with a cancelled task.
      */
     @Test
-    public void testShutdownOnSuccess5() throws Exception {
+    void testShutdownOnSuccess5() throws Exception {
         try (var scope = new ShutdownOnSuccess<String>()) {
 
             // cancelled task
@@ -1137,7 +1180,7 @@ public class StructuredTaskScopeTest {
             scope.join();
 
             assertThrows(CancellationException.class, () -> scope.result());
-            Throwable ex = expectThrows(FooException.class,
+            Throwable ex = assertThrows(FooException.class,
                                         () -> scope.result(e -> new FooException(e)));
             assertTrue(ex.getCause() instanceof CancellationException);
         }
@@ -1147,7 +1190,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnFailure with no completed tasks.
      */
     @Test
-    public void testShutdownOnFailure1() throws Throwable {
+    void testShutdownOnFailure1() throws Throwable {
         try (var scope = new ShutdownOnFailure()) {
             assertTrue(scope.exception().isEmpty());
             scope.throwIfFailed();
@@ -1159,7 +1202,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnFailure with tasks that completed normally.
      */
     @Test
-    public void testShutdownOnFailure2() throws Throwable {
+    void testShutdownOnFailure2() throws Throwable {
         try (var scope = new ShutdownOnFailure()) {
             scope.fork(() -> "foo");
             scope.fork(() -> "bar");
@@ -1176,7 +1219,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnFailure with tasks that completed normally and abnormally.
      */
     @Test
-    public void testShutdownOnFailure3() throws Throwable {
+    void testShutdownOnFailure3() throws Throwable {
         try (var scope = new ShutdownOnFailure()) {
 
             // one task completes normally, the other with an exception
@@ -1187,10 +1230,10 @@ public class StructuredTaskScopeTest {
             Throwable ex = scope.exception().orElse(null);
             assertTrue(ex instanceof ArithmeticException);
 
-            ex = expectThrows(ExecutionException.class, () -> scope.throwIfFailed());
+            ex = assertThrows(ExecutionException.class, () -> scope.throwIfFailed());
             assertTrue(ex.getCause() instanceof ArithmeticException);
 
-            ex = expectThrows(FooException.class,
+            ex = assertThrows(FooException.class,
                               () -> scope.throwIfFailed(e -> new FooException(e)));
             assertTrue(ex.getCause() instanceof ArithmeticException);
         }
@@ -1200,7 +1243,7 @@ public class StructuredTaskScopeTest {
      * Test ShutdownOnFailure with a cancelled task.
      */
     @Test
-    public void testShutdownOnFailure4() throws Throwable {
+    void testShutdownOnFailure4() throws Throwable {
         try (var scope = new ShutdownOnFailure()) {
 
             var future = scope.fork(() -> {
@@ -1216,7 +1259,7 @@ public class StructuredTaskScopeTest {
 
             assertThrows(CancellationException.class, () -> scope.throwIfFailed());
 
-            ex = expectThrows(FooException.class,
+            ex = assertThrows(FooException.class,
                               () -> scope.throwIfFailed(e -> new FooException(e)));
             assertTrue(ex.getCause() instanceof CancellationException);
         }
diff --git a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredThreadDumpTest.java b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredThreadDumpTest.java
index be737170e83..76e1bbd364e 100644
--- a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredThreadDumpTest.java
+++ b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/StructuredThreadDumpTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,7 +28,7 @@
  * @enablePreview
  * @modules jdk.incubator.concurrent
  * @library /test/lib
- * @run testng/othervm StructuredThreadDumpTest
+ * @run junit/othervm StructuredThreadDumpTest
  */
 
 import jdk.incubator.concurrent.StructuredTaskScope;
@@ -43,17 +43,17 @@ import java.util.stream.Stream;
 import com.sun.management.HotSpotDiagnosticMXBean;
 import com.sun.management.HotSpotDiagnosticMXBean.ThreadDumpFormat;
 import jdk.test.lib.threaddump.ThreadDump;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class StructuredThreadDumpTest {
+class StructuredThreadDumpTest {
 
     /**
      * Test that a thread dump with a tree of task scopes contains a thread grouping for
      * each task scope.
      */
     @Test
-    public void testTree() throws Exception {
+    void testTree() throws Exception {
         ThreadFactory factory = Thread.ofVirtual().factory();
         try (var scope = new StructuredTaskScope<>("scope", factory)) {
             Thread thread1 = fork(scope, "child-scope-A");
@@ -95,7 +95,7 @@ public class StructuredThreadDumpTest {
      * each task scope.
      */
     @Test
-    public void testNested() throws Exception {
+    void testNested() throws Exception {
         ThreadFactory factory = Thread.ofVirtual().factory();
         try (var scope1 = new StructuredTaskScope<>("scope-A", factory)) {
             Thread thread1 = fork(scope1);
diff --git a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/WithScopedValue.java b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/WithScopedValue.java
index a6917ccf6ab..7bb0b888b94 100644
--- a/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/WithScopedValue.java
+++ b/test/jdk/jdk/incubator/concurrent/StructuredTaskScope/WithScopedValue.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,7 +26,7 @@
  * @summary Basic tests for StructuredTaskScope with scoped values
  * @enablePreview
  * @modules jdk.incubator.concurrent
- * @run testng WithScopedValue
+ * @run junit WithScopedValue
  */
 
 import jdk.incubator.concurrent.ScopedValue;
@@ -35,27 +35,25 @@ import jdk.incubator.concurrent.StructureViolationException;
 import java.util.concurrent.Future;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.stream.Stream;
 
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
 
-@Test
-public class WithScopedValue {
+class WithScopedValue {
 
-    @DataProvider
-    public Object[][] factories() {
-        return new Object[][] {
-                { Thread.ofPlatform().factory() },
-                { Thread.ofVirtual().factory() },
-        };
+    private static Stream<ThreadFactory> factories() {
+        return Stream.of(Thread.ofPlatform().factory(), Thread.ofVirtual().factory());
     }
 
     /**
      * Test that fork inherits a scoped value into a child thread.
      */
-    @Test(dataProvider = "factories")
-    public void testForkInheritsScopedValue1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testForkInheritsScopedValue1(ThreadFactory factory) throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         String value = ScopedValue.where(name, "x", () -> {
             try (var scope = new StructuredTaskScope<String>(null, factory)) {
@@ -72,8 +70,9 @@ public class WithScopedValue {
     /**
      * Test that fork inherits a scoped value into a grandchild thread.
      */
-    @Test(dataProvider = "factories")
-    public void testForkInheritsScopedValue2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testForkInheritsScopedValue2(ThreadFactory factory) throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         String value = ScopedValue.where(name, "x", () -> {
             try (var scope1 = new StructuredTaskScope<String>(null, factory)) {
@@ -96,8 +95,9 @@ public class WithScopedValue {
     /**
      * Test that fork inherits a rebound scoped value into a grandchild thread.
      */
-    @Test(dataProvider = "factories")
-    public void testForkInheritsScopedValue3(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testForkInheritsScopedValue3(ThreadFactory factory) throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         String value = ScopedValue.where(name, "x", () -> {
             try (var scope1 = new StructuredTaskScope<String>(null, factory)) {
@@ -128,7 +128,8 @@ public class WithScopedValue {
     /**
      * Test exiting a dynamic scope with an open task scope.
      */
-    public void testStructureViolation1() throws Exception {
+    @Test
+    void testStructureViolation1() throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         class Box {
             StructuredTaskScope<Object> scope;
@@ -164,7 +165,8 @@ public class WithScopedValue {
     /**
      * Test closing a StructuredTaskScope while executing in a dynamic scope.
      */
-    public void testStructureViolation2() throws Exception {
+    @Test
+    void testStructureViolation2() throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         try (var scope = new StructuredTaskScope<String>()) {
             ScopedValue.where(name, "x", () -> {
@@ -176,7 +178,8 @@ public class WithScopedValue {
     /**
      * Test fork when a scoped value is bound after a StructuredTaskScope is created.
      */
-    public void testStructureViolation3() throws Exception {
+    @Test
+    void testStructureViolation3() throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         try (var scope = new StructuredTaskScope<String>()) {
             ScopedValue.where(name, "x", () -> {
@@ -189,7 +192,8 @@ public class WithScopedValue {
     /**
      * Test fork when a scoped value is re-bound after a StructuredTaskScope is created.
      */
-    public void testStructureViolation4() throws Exception {
+    @Test
+    void testStructureViolation4() throws Exception {
         ScopedValue<String> name1 = ScopedValue.newInstance();
         ScopedValue<String> name2 = ScopedValue.newInstance();
 
diff --git a/test/jdk/jdk/internal/misc/ThreadFlock/ThreadFlockTest.java b/test/jdk/jdk/internal/misc/ThreadFlock/ThreadFlockTest.java
index 45cfac628db..dcaa3c5a78b 100644
--- a/test/jdk/jdk/internal/misc/ThreadFlock/ThreadFlockTest.java
+++ b/test/jdk/jdk/internal/misc/ThreadFlock/ThreadFlockTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,14 +26,14 @@
  * @summary Basic tests for ThreadFlock
  * @modules java.base/jdk.internal.misc
  * @enablePreview
- * @run testng/othervm -DthreadFactory=platform ThreadFlockTest
+ * @run junit/othervm -DthreadFactory=platform ThreadFlockTest
  */
 
 /*
  * @test id=virtual
  * @modules java.base/jdk.internal.misc
  * @enablePreview
- * @run testng/othervm -DthreadFactory=virtual ThreadFlockTest
+ * @run junit/othervm -DthreadFactory=virtual ThreadFlockTest
  */
 
 import java.time.Duration;
@@ -43,26 +43,23 @@ import java.util.concurrent.*;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import jdk.internal.misc.ThreadFlock;
 
-import org.testng.annotations.AfterClass;
-import org.testng.annotations.BeforeClass;
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
 
-public class ThreadFlockTest {
-    private ScheduledExecutorService scheduler;
-    private Object[][] threadFactories;
+class ThreadFlockTest {
+    private static ScheduledExecutorService scheduler;
+    private static List<ThreadFactory> threadFactories;
 
-    @BeforeClass
-    public void setUp() throws Exception {
-        ThreadFactory factory = (task) -> {
-            Thread thread = new Thread(task);
-            thread.setDaemon(true);
-            return thread;
-        };
-        this.scheduler = Executors.newSingleThreadScheduledExecutor(factory);
+    @BeforeAll
+    static void setup() throws Exception {
+        scheduler = Executors.newSingleThreadScheduledExecutor();
 
         // thread factories
         String value = System.getProperty("threadFactory");
@@ -72,35 +69,32 @@ public class ThreadFlockTest {
         if (value == null || value.equals("virtual"))
             list.add(Thread.ofVirtual().factory());
         assertTrue(list.size() > 0, "No thread factories for tests");
-        this.threadFactories = list.stream()
-                .map(f -> new Object[] { f })
-                .toArray(Object[][]::new);
+        threadFactories = list;
     }
 
-    @AfterClass
-    public void tearDown() {
+    @AfterAll
+    static void shutdown() {
         scheduler.shutdown();
     }
 
-    @DataProvider(name = "factories")
-    public Object[][] factories() {
-        return threadFactories;
+    private static Stream<ThreadFactory> factories() {
+        return threadFactories.stream();
     }
 
     /**
      * Test ThreadFlock::name.
      */
     @Test
-    public void testName() {
+    void testName() {
         try (var flock = ThreadFlock.open(null)) {
-            assertEquals(flock.name(), null);
+            assertNull(flock.name());
             flock.close();
-            assertEquals(flock.name(), null);  // after close
+            assertNull(flock.name());  // after close
         }
         try (var flock = ThreadFlock.open("fetcher")) {
-            assertEquals(flock.name(), "fetcher");
+            assertEquals("fetcher", flock.name());
             flock.close();
-            assertEquals(flock.name(), "fetcher");  // after close
+            assertEquals("fetcher", flock.name());  // after close
         }
     }
 
@@ -108,7 +102,7 @@ public class ThreadFlockTest {
      * Test ThreadFlock::owner.
      */
     @Test
-    public void testOwner() {
+    void testOwner() {
         try (var flock = ThreadFlock.open(null)) {
             assertTrue(flock.owner() == Thread.currentThread());
             flock.close();
@@ -120,7 +114,7 @@ public class ThreadFlockTest {
      * Test ThreadFlock::isXXXX methods.
      */
     @Test
-    public void testState() {
+    void testState() {
         try (var flock = ThreadFlock.open(null)) {
             assertFalse(flock.isShutdown());
             assertFalse(flock.isClosed());
@@ -141,8 +135,9 @@ public class ThreadFlockTest {
     /**
      * Test ThreadFlock::threads enumerates all threads.
      */
-    @Test(dataProvider = "factories")
-    public void testThreads(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testThreads(ThreadFactory factory) {
         CountDownLatch latch = new CountDownLatch(1);
         var exception = new AtomicReference<Exception>();
         Runnable awaitLatch = () -> {
@@ -166,21 +161,22 @@ public class ThreadFlockTest {
             }
 
             // check thread ThreadFlock::threads enumerates all threads
-            assertEquals(threads, flock.threads().collect(Collectors.toSet()));
+            assertEquals(flock.threads().collect(Collectors.toSet()), threads);
 
         } finally {
             latch.countDown();  // release threads
             flock.close();
         }
         assertTrue(flock.threads().count() == 0);
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test ThreadFlock::containsThread with nested flocks.
      */
-    @Test(dataProvider = "factories")
-    public void testContainsThread1(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testContainsThread1(ThreadFactory factory) {
         CountDownLatch latch = new CountDownLatch(1);
         var exception = new AtomicReference<Exception>();
 
@@ -222,8 +218,9 @@ public class ThreadFlockTest {
     /**
      * Test ThreadFlock::containsThread with a tree of flocks.
      */
-    @Test(dataProvider = "factories")
-    public void testContainsThread2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testContainsThread2(ThreadFactory factory) throws Exception {
         CountDownLatch latch = new CountDownLatch(1);
         var exception = new AtomicReference<Exception>();
 
@@ -276,8 +273,9 @@ public class ThreadFlockTest {
     /**
      * Test that start causes a thread to execute.
      */
-    @Test(dataProvider = "factories")
-    public void testStart(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testStart(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             AtomicBoolean executed = new AtomicBoolean();
             Thread thread = factory.newThread(() -> executed.set(true));
@@ -290,44 +288,48 @@ public class ThreadFlockTest {
     /**
      * Test that start throws IllegalStateException when shutdown
      */
-    @Test(dataProvider = "factories")
-    public void testStartAfterShutdown(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testStartAfterShutdown(ThreadFactory factory) {
         try (var flock = ThreadFlock.open(null)) {
             flock.shutdown();
             Thread thread = factory.newThread(() -> { });
-            expectThrows(IllegalStateException.class, () -> flock.start(thread));
+            assertThrows(IllegalStateException.class, () -> flock.start(thread));
         }
     }
 
     /**
      * Test that start throws IllegalStateException when closed
      */
-    @Test(dataProvider = "factories")
-    public void testStartAfterClose(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testStartAfterClose(ThreadFactory factory) {
         var flock = ThreadFlock.open(null);
         flock.close();;
         Thread thread = factory.newThread(() -> { });
-        expectThrows(IllegalStateException.class, () -> flock.start(thread));
+        assertThrows(IllegalStateException.class, () -> flock.start(thread));
     }
 
     /**
      * Test that start throws IllegalThreadStateException when invoked to
      * start a thread that has already started.
      */
-    @Test(dataProvider = "factories")
-    public void testStartAfterStarted(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testStartAfterStarted(ThreadFactory factory) {
         try (var flock = ThreadFlock.open(null)) {
             Thread thread = factory.newThread(() -> { });
             flock.start(thread);
-            expectThrows(IllegalThreadStateException.class, () -> flock.start(thread));
+            assertThrows(IllegalThreadStateException.class, () -> flock.start(thread));
         }
     }
 
     /**
      * Test start is confined to threads in the flock.
      */
-    @Test(dataProvider = "factories")
-    public void testStartConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testStartConfined(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             // thread in flock
             testStartConfined(flock, task -> {
@@ -370,7 +372,7 @@ public class ThreadFlockTest {
         thread.join();
         Throwable cause = exception.get();
         if (flock.containsThread(thread)) {
-            assertTrue(cause == null);
+            assertNull(cause);
         } else {
             assertTrue(cause instanceof WrongThreadException);
         }
@@ -380,7 +382,7 @@ public class ThreadFlockTest {
      * Test awaitAll with no threads.
      */
     @Test
-    public void testAwaitAllWithNoThreads() throws Exception {
+    void testAwaitAllWithNoThreads() throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             assertTrue(flock.awaitAll());
             assertTrue(flock.awaitAll(Duration.ofSeconds(1)));
@@ -390,8 +392,9 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll with threads running.
      */
-    @Test(dataProvider = "factories")
-    public void testAwaitAllWithThreads(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testAwaitAllWithThreads(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             AtomicBoolean done = new AtomicBoolean();
             Runnable task = () -> {
@@ -410,8 +413,9 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll with timeout, threads finish before timeout expires.
      */
-    @Test(dataProvider = "factories")
-    public void testAwaitAllWithTimeout1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testAwaitAllWithTimeout1(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             Runnable task = () -> {
                 try {
@@ -431,12 +435,15 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll with timeout, timeout expires before threads finish.
      */
-    @Test(dataProvider = "factories")
-    public void testAwaitAllWithTimeout2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testAwaitAllWithTimeout2(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
+            var latch = new CountDownLatch(1);
+
             Runnable task = () -> {
                 try {
-                    Thread.sleep(Duration.ofSeconds(30));
+                    latch.await();
                 } catch (InterruptedException e) { }
             };
             Thread thread = factory.newThread(task);
@@ -451,7 +458,7 @@ public class ThreadFlockTest {
                     checkDuration(startMillis, 1900, 4000);
                 }
             } finally {
-                thread.interrupt();
+                latch.countDown();
             }
         }
     }
@@ -459,12 +466,15 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll with timeout many times.
      */
-    @Test(dataProvider = "factories")
-    public void testAwaitAllWithTimeout3(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testAwaitAllWithTimeout3(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
+            var latch = new CountDownLatch(1);
+
             Runnable task = () -> {
                 try {
-                    Thread.sleep(Duration.ofSeconds(30));
+                    latch.await();
                 } catch (InterruptedException e) { }
             };
             Thread thread = factory.newThread(task);
@@ -478,7 +488,7 @@ public class ThreadFlockTest {
                     } catch (TimeoutException expected) { }
                 }
             } finally {
-                thread.interrupt();
+                latch.countDown();
             }
 
             boolean done = flock.awaitAll();
@@ -489,12 +499,15 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll with a 0 or negative timeout.
      */
-    @Test(dataProvider = "factories")
-    public void testAwaitAllWithTimeout4(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testAwaitAllWithTimeout4(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
+            var latch = new CountDownLatch(1);
+
             Runnable task = () -> {
                 try {
-                    Thread.sleep(Duration.ofSeconds(30));
+                    latch.await();
                 } catch (InterruptedException e) { }
             };
             Thread thread = factory.newThread(task);
@@ -510,7 +523,7 @@ public class ThreadFlockTest {
                     fail("awaitAll did not throw");
                 } catch (TimeoutException expected) { }
             } finally {
-                thread.interrupt();
+                latch.countDown();
             }
 
             boolean done = flock.awaitAll();
@@ -521,8 +534,9 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll with interrupt status set, should interrupt thread.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptAwaitAll1(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptAwaitAll1(ThreadFactory factory) {
         CountDownLatch latch = new CountDownLatch(1);
         var exception = new AtomicReference<Exception>();
         Runnable awaitLatch = () -> {
@@ -568,14 +582,15 @@ public class ThreadFlockTest {
         }
 
         // thread should not have throw any exception
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test interrupt of awaitAll.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptAwaitAll2(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptAwaitAll2(ThreadFactory factory) {
         CountDownLatch latch = new CountDownLatch(1);
         var exception = new AtomicReference<Exception>();
         Runnable awaitLatch = () -> {
@@ -619,14 +634,14 @@ public class ThreadFlockTest {
         }
 
         // thread should not have throw any exception
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test awaitAll after close.
      */
     @Test
-    public void testAwaitAfterClose() throws Exception {
+    void testAwaitAfterClose() throws Exception {
         var flock = ThreadFlock.open(null);
         flock.close();
         assertTrue(flock.awaitAll());
@@ -636,8 +651,9 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll is flock confined.
      */
-    @Test(dataProvider = "factories")
-    public void testAwaitAllConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testAwaitAllConfined(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             // thread in flock
             testAwaitAllConfined(flock, task -> {
@@ -676,8 +692,9 @@ public class ThreadFlockTest {
     /**
      * Test awaitAll with the wakeup permit.
      */
-    @Test(dataProvider = "factories")
-    public void testWakeupAwaitAll1(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testWakeupAwaitAll1(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             CountDownLatch latch = new CountDownLatch(1);
             var exception = new AtomicReference<Exception>();
@@ -704,8 +721,9 @@ public class ThreadFlockTest {
     /**
      * Schedule a thread to wakeup the owner waiting in awaitAll.
      */
-    @Test(dataProvider = "factories")
-    public void testWakeupAwaitAll2(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testWakeupAwaitAll2(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             CountDownLatch latch = new CountDownLatch(1);
             var exception = new AtomicReference<Exception>();
@@ -737,8 +755,9 @@ public class ThreadFlockTest {
     /**
      * Test wakeup is flock confined.
      */
-    @Test(dataProvider = "factories")
-    public void testWakeupConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testWakeupConfined(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             // thread in flock
             testWakeupConfined(flock, task -> {
@@ -772,7 +791,7 @@ public class ThreadFlockTest {
         thread.join();
         Throwable cause = exception.get();
         if (flock.containsThread(thread)) {
-            assertTrue(cause == null);
+            assertNull(cause);
         } else {
             assertTrue(cause instanceof WrongThreadException);
         }
@@ -782,7 +801,7 @@ public class ThreadFlockTest {
      * Test close with no threads running.
      */
     @Test
-    public void testCloseWithNoThreads() {
+    void testCloseWithNoThreads() {
         var flock = ThreadFlock.open(null);
         flock.close();
         assertTrue(flock.isClosed());
@@ -792,8 +811,9 @@ public class ThreadFlockTest {
     /**
      * Test close with threads running.
      */
-    @Test(dataProvider = "factories")
-    public void testCloseWithThreads(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCloseWithThreads(ThreadFactory factory) {
         var exception = new AtomicReference<Exception>();
         Runnable sleepTask = () -> {
             try {
@@ -811,14 +831,14 @@ public class ThreadFlockTest {
         }
         assertTrue(flock.isClosed());
         assertTrue(flock.threads().count() == 0);
-        assertTrue(exception.get() == null); // no exception thrown
+        assertNull(exception.get()); // no exception thrown
     }
 
     /**
      * Test close after flock is closed.
      */
     @Test
-    public void testCloseAfterClose() {
+    void testCloseAfterClose() {
         var flock = ThreadFlock.open(null);
         flock.close();
         assertTrue(flock.isClosed());
@@ -829,8 +849,9 @@ public class ThreadFlockTest {
     /**
      * Test close is owner confined.
      */
-    @Test(dataProvider = "factories")
-    public void testCloseConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testCloseConfined(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             // thread in flock
             testCloseConfined(flock, task -> {
@@ -869,8 +890,9 @@ public class ThreadFlockTest {
     /**
      * Test close with interrupt status set, should not interrupt threads.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptClose1(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptClose1(ThreadFactory factory) {
         var exception = new AtomicReference<Exception>();
         Runnable sleepTask = () -> {
             try {
@@ -886,14 +908,15 @@ public class ThreadFlockTest {
         } finally {
             assertTrue(Thread.interrupted());  // clear interrupt
         }
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test interrupt thread block in close.
      */
-    @Test(dataProvider = "factories")
-    public void testInterruptClose2(ThreadFactory factory) {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInterruptClose2(ThreadFactory factory) {
         var exception = new AtomicReference<Exception>();
         Runnable sleepTask = () -> {
             try {
@@ -909,14 +932,15 @@ public class ThreadFlockTest {
         } finally {
             assertTrue(Thread.interrupted());  // clear interrupt
         }
-        assertTrue(exception.get() == null);
+        assertNull(exception.get());
     }
 
     /**
      * Test shutdown is confined to threads in the flock.
      */
-    @Test(dataProvider = "factories")
-    public void testShutdownConfined(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testShutdownConfined(ThreadFactory factory) throws Exception {
         try (var flock = ThreadFlock.open(null)) {
             // thread in flock
             testShutdownConfined(flock, task -> {
@@ -958,7 +982,7 @@ public class ThreadFlockTest {
         thread.join();
         Throwable cause = exception.get();
         if (flock.containsThread(thread)) {
-            assertTrue(cause == null);
+            assertNull(cause);
         } else {
             assertTrue(cause instanceof WrongThreadException);
         }
@@ -968,7 +992,7 @@ public class ThreadFlockTest {
      * Test that closing an enclosing thread flock closes a nested thread flocks.
      */
     @Test
-    public void testStructureViolation() {
+    void testStructureViolation() {
         try (var flock1 = ThreadFlock.open("flock1")) {
             try (var flock2 = ThreadFlock.open("flock2")) {
                 try {
@@ -986,8 +1010,9 @@ public class ThreadFlockTest {
     /**
      * Test Thread exiting with an open flock. The exiting thread should close the flock.
      */
-    @Test(dataProvider = "factories")
-    public void testThreadExitWithOpenFlock(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testThreadExitWithOpenFlock(ThreadFactory factory) throws Exception {
         var flockRef = new AtomicReference<ThreadFlock>();
         var childRef = new AtomicReference<Thread>();
 
@@ -1017,7 +1042,7 @@ public class ThreadFlockTest {
      * Test toString includes the flock name.
      */
     @Test
-    public void testToString() {
+    void testToString() {
         try (var flock = ThreadFlock.open("xxxx")) {
             assertTrue(flock.toString().contains("xxx"));
         }
@@ -1027,11 +1052,11 @@ public class ThreadFlockTest {
      * Test for NullPointerException.
      */
     @Test
-    public void testNulls() {
+    void testNulls() {
         try (var flock = ThreadFlock.open(null)) {
-            expectThrows(NullPointerException.class, () -> flock.start(null));
-            expectThrows(NullPointerException.class, () -> flock.awaitAll(null));
-            expectThrows(NullPointerException.class, () -> flock.containsThread(null));
+            assertThrows(NullPointerException.class, () -> flock.start(null));
+            assertThrows(NullPointerException.class, () -> flock.awaitAll(null));
+            assertThrows(NullPointerException.class, () -> flock.containsThread(null));
         }
     }
 
diff --git a/test/jdk/jdk/internal/misc/ThreadFlock/WithScopedValue.java b/test/jdk/jdk/internal/misc/ThreadFlock/WithScopedValue.java
index 7bb45bd6f79..32fce35cccb 100644
--- a/test/jdk/jdk/internal/misc/ThreadFlock/WithScopedValue.java
+++ b/test/jdk/jdk/internal/misc/ThreadFlock/WithScopedValue.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -27,38 +27,33 @@
  * @enablePreview
  * @modules java.base/jdk.internal.misc
  * @modules jdk.incubator.concurrent
- * @run testng WithScopedValue
+ * @run junit WithScopedValue
  */
 
 import jdk.internal.misc.ThreadFlock;
 import jdk.incubator.concurrent.ScopedValue;
 import jdk.incubator.concurrent.StructureViolationException;
-import java.util.concurrent.Executors;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.atomic.AtomicReference;
+import java.util.stream.Stream;
 
-import org.testng.annotations.DataProvider;
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+import static org.junit.jupiter.api.Assertions.*;
 
-@Test
-public class WithScopedValue {
+class WithScopedValue {
 
-    @DataProvider(name = "factories")
-    public Object[][] factories() {
-        var defaultThreadFactory = Executors.defaultThreadFactory();
-        var virtualThreadFactory = Thread.ofVirtual().factory();
-        return new Object[][]{
-                { defaultThreadFactory, },
-                { virtualThreadFactory, },
-        };
+    private static Stream<ThreadFactory> factories() {
+        return Stream.of(Thread.ofPlatform().factory(), Thread.ofVirtual().factory());
     }
 
     /**
      * Test inheritance of a scoped value.
      */
-    @Test(dataProvider = "factories")
-    public void testInheritsScopedValue(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testInheritsScopedValue(ThreadFactory factory) throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         String value = ScopedValue.where(name, "duke", () -> {
             var result = new AtomicReference<String>();
@@ -71,13 +66,14 @@ public class WithScopedValue {
             }
             return result.get();
         });
-        assertEquals(value, "duke");
+        assertEquals("duke", value);
     }
 
     /**
      * Test exiting a dynamic scope with open thread flocks.
      */
-    public void testStructureViolation1() {
+    @Test
+    void testStructureViolation1() {
         ScopedValue<String> name = ScopedValue.newInstance();
         class Box {
             ThreadFlock flock1;
@@ -99,7 +95,8 @@ public class WithScopedValue {
      * Test closing a thread flock while in a dynamic scope and with enclosing thread
      * flocks. This test closes enclosing flock1.
      */
-    public void testStructureViolation2() {
+    @Test
+    void testStructureViolation2() {
         ScopedValue<String> name = ScopedValue.newInstance();
         try (var flock1 = ThreadFlock.open("flock1")) {
             ScopedValue.where(name, "x1", () -> {
@@ -130,7 +127,8 @@ public class WithScopedValue {
      * Test closing a thread flock while in a dynamic scope and with enclosing thread
      * flocks. This test closes enclosing flock2.
      */
-    public void testStructureViolation3() {
+    @Test
+    void testStructureViolation3() {
         ScopedValue<String> name = ScopedValue.newInstance();
         try (var flock1 = ThreadFlock.open("flock1")) {
             ScopedValue.where(name, "x1", () -> {
@@ -161,7 +159,8 @@ public class WithScopedValue {
      * Test closing a thread flock while in a dynamic scope and with enclosing thread
      * flocks. This test closes enclosing flock3.
      */
-    public void testStructureViolation4() {
+    @Test
+    void testStructureViolation4() {
         ScopedValue<String> name = ScopedValue.newInstance();
         try (var flock1 = ThreadFlock.open("flock1")) {
             ScopedValue.where(name, "x1", () -> {
@@ -191,13 +190,14 @@ public class WithScopedValue {
     /**
      * Test start when a scoped value is bound after a thread flock is created.
      */
-    @Test(dataProvider = "factories")
-    public void testStructureViolation5(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testStructureViolation5(ThreadFactory factory) throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         try (var flock = ThreadFlock.open(null)) {
             ScopedValue.where(name, "duke", () -> {
                 Thread thread = factory.newThread(() -> { });
-                expectThrows(StructureViolationException.class, () -> flock.start(thread));
+                assertThrows(StructureViolationException.class, () -> flock.start(thread));
             });
         }
     }
@@ -205,14 +205,15 @@ public class WithScopedValue {
     /**
      * Test start when a scoped value is re-bound after a thread flock is created.
      */
-    @Test(dataProvider = "factories")
-    public void testStructureViolation6(ThreadFactory factory) throws Exception {
+    @ParameterizedTest
+    @MethodSource("factories")
+    void testStructureViolation6(ThreadFactory factory) throws Exception {
         ScopedValue<String> name = ScopedValue.newInstance();
         ScopedValue.where(name, "duke", () -> {
             try (var flock = ThreadFlock.open(null)) {
                 ScopedValue.where(name, "duchess", () -> {
                     Thread thread = factory.newThread(() -> { });
-                    expectThrows(StructureViolationException.class, () -> flock.start(thread));
+                    assertThrows(StructureViolationException.class, () -> flock.start(thread));
                 });
             }
         });