8076287: Performance degradation observed with TimeZone Benchmark

Reviewed-by: okutsu

jdk/src/java.base/share/classes/sun/util/locale/provider/LocaleResources.java

@@ -47,6 +47,7 @@ import java.util.Calendar;
 import java.util.LinkedHashSet;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Objects;
 import java.util.ResourceBundle;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
@@ -250,17 +251,17 @@ public class LocaleResources {
         return (String) localeName;
     }
 
-    String[] getTimeZoneNames(String key, int size) {
+    String[] getTimeZoneNames(String key) {
         String[] names = null;
-        String cacheKey = TIME_ZONE_NAMES + size + '.' + key;
+        String cacheKey = TIME_ZONE_NAMES + '.' + key;
 
         removeEmptyReferences();
         ResourceReference data = cache.get(cacheKey);
 
-        if (data == null || ((names = (String[]) data.get()) == null)) {
+        if (Objects.isNull(data) || Objects.isNull((names = (String[]) data.get()))) {
             TimeZoneNamesBundle tznb = localeData.getTimeZoneNames(locale);
             if (tznb.containsKey(key)) {
-                names = tznb.getStringArray(key, size);
+                names = tznb.getStringArray(key);
                 cache.put(cacheKey,
                           new ResourceReference(cacheKey, (Object) names, referenceQueue));
             }

jdk/src/java.base/share/classes/sun/util/locale/provider/TimeZoneNameProviderImpl.java

@@ -26,6 +26,7 @@
 package sun.util.locale.provider;
 
 import java.util.Locale;
+import java.util.Objects;
 import java.util.Set;
 import java.util.TimeZone;
 import java.util.spi.TimeZoneNameProvider;
@@ -95,8 +96,9 @@ public class TimeZoneNameProviderImpl extends TimeZoneNameProvider {
      */
     @Override
     public String getDisplayName(String id, boolean daylight, int style, Locale locale) {
-        String[] names = getDisplayNameArray(id, 5, locale);
+        String[] names = getDisplayNameArray(id, locale);
-        if (names != null) {
+        if (Objects.nonNull(names)) {
+            assert names.length >= 7;
             int index = daylight ? 3 : 1;
             if (style == TimeZone.SHORT) {
                 index++;
@@ -108,18 +110,18 @@ public class TimeZoneNameProviderImpl extends TimeZoneNameProvider {
 
     @Override
     public String getGenericDisplayName(String id, int style, Locale locale) {
-        String[] names = getDisplayNameArray(id, 7, locale);
+        String[] names = getDisplayNameArray(id, locale);
-        if (names != null && names.length >= 7) {
+        if (Objects.nonNull(names)) {
+            assert names.length >= 7;
             return names[(style == TimeZone.LONG) ? 5 : 6];
         }
         return null;
     }
 
-    private String[] getDisplayNameArray(String id, int n, Locale locale) {
+    private String[] getDisplayNameArray(String id, Locale locale) {
-        if (id == null || locale == null) {
+        Objects.requireNonNull(id);
-            throw new NullPointerException();
+        Objects.requireNonNull(locale);
-        }
+        return LocaleProviderAdapter.forType(type).getLocaleResources(locale).getTimeZoneNames(id);
-        return LocaleProviderAdapter.forType(type).getLocaleResources(locale).getTimeZoneNames(id, n);
     }
 
     /**

jdk/src/java.base/share/classes/sun/util/locale/provider/TimeZoneNameUtility.java

@@ -30,6 +30,7 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.spi.TimeZoneNameProvider;
@@ -100,9 +101,9 @@ public final class TimeZoneNameUtility {
      * Retrieve display names for a time zone ID.
      */
     public static String[] retrieveDisplayNames(String id, Locale locale) {
-        if (id == null || locale == null) {
+        Objects.requireNonNull(id);
-            throw new NullPointerException();
+        Objects.requireNonNull(locale);
-        }
+
         return retrieveDisplayNamesImpl(id, locale);
     }
 
@@ -115,9 +116,12 @@ public final class TimeZoneNameUtility {
      * @return the requested generic time zone display name, or null if not found.
      */
     public static String retrieveGenericDisplayName(String id, int style, Locale locale) {
-        LocaleServiceProviderPool pool =
+        String[] names = retrieveDisplayNamesImpl(id, locale);
-            LocaleServiceProviderPool.getPool(TimeZoneNameProvider.class);
+        if (Objects.nonNull(names)) {
-        return pool.getLocalizedObject(TimeZoneNameGetter.INSTANCE, locale, "generic", style, id);
+            return names[6 - style];
+        } else {
+            return null;
+        }
     }
 
     /**
@@ -130,140 +134,53 @@ public final class TimeZoneNameUtility {
      * @return the requested time zone name, or null if not found.
      */
     public static String retrieveDisplayName(String id, boolean daylight, int style, Locale locale) {
-        LocaleServiceProviderPool pool =
+        String[] names = retrieveDisplayNamesImpl(id, locale);
-            LocaleServiceProviderPool.getPool(TimeZoneNameProvider.class);
+        if (Objects.nonNull(names)) {
-        return pool.getLocalizedObject(TimeZoneNameGetter.INSTANCE, locale, daylight ? "dst" : "std", style, id);
+            return names[(daylight ? 4 : 2) - style];
+        } else {
+            return null;
+        }
     }
 
     private static String[] retrieveDisplayNamesImpl(String id, Locale locale) {
         LocaleServiceProviderPool pool =
             LocaleServiceProviderPool.getPool(TimeZoneNameProvider.class);
+        String[] names;
+        Map<Locale, String[]> perLocale = null;
 
         SoftReference<Map<Locale, String[]>> ref = cachedDisplayNames.get(id);
-        if (ref != null) {
+        if (Objects.nonNull(ref)) {
-            Map<Locale, String[]> perLocale = ref.get();
+            perLocale = ref.get();
-            if (perLocale != null) {
+            if (Objects.nonNull(perLocale)) {
-                String[] names = perLocale.get(locale);
+                names = perLocale.get(locale);
-                if (names != null) {
+                if (Objects.nonNull(names)) {
                     return names;
                 }
-                names = pool.getLocalizedObject(TimeZoneNameArrayGetter.INSTANCE, locale, id);
-                if (names != null) {
-                    perLocale.put(locale, names);
-                }
-                return names;
             }
         }
 
-        String[] names = pool.getLocalizedObject(TimeZoneNameArrayGetter.INSTANCE, locale, id);
+        // build names array
-        if (names != null) {
+        names = new String[7];
-            Map<Locale, String[]> perLocale = new ConcurrentHashMap<>();
+        names[0] = id;
-            perLocale.put(locale, names);
+        for (int i = 1; i <= 6; i ++) {
-            ref = new SoftReference<>(perLocale);
+            names[i] = pool.getLocalizedObject(TimeZoneNameGetter.INSTANCE, locale,
-            cachedDisplayNames.put(id, ref);
+                    i<5 ? (i<3 ? "std" : "dst") : "generic", i%2, id);
         }
+
+        if (Objects.isNull(perLocale)) {
+            perLocale = new ConcurrentHashMap<>();
+        }
+        perLocale.put(locale, names);
+        ref = new SoftReference<>(perLocale);
+        cachedDisplayNames.put(id, ref);
         return names;
     }
 
+
     /**
      * Obtains a localized time zone strings from a TimeZoneNameProvider
      * implementation.
      */
-    private static class TimeZoneNameArrayGetter
-        implements LocaleServiceProviderPool.LocalizedObjectGetter<TimeZoneNameProvider,
-                                                                   String[]>{
-        private static final TimeZoneNameArrayGetter INSTANCE =
-            new TimeZoneNameArrayGetter();
-
-        @Override
-        public String[] getObject(TimeZoneNameProvider timeZoneNameProvider,
-                                  Locale locale,
-                                  String requestID,
-                                  Object... params) {
-            assert params.length == 0;
-
-            // First, try to get names with the request ID
-            String[] names = buildZoneStrings(timeZoneNameProvider, locale, requestID);
-
-            if (names == null) {
-                Map<String, String> aliases = ZoneInfo.getAliasTable();
-
-                if (aliases != null) {
-                    // Check whether this id is an alias, if so,
-                    // look for the standard id.
-                    String canonicalID = aliases.get(requestID);
-                    if (canonicalID != null) {
-                        names = buildZoneStrings(timeZoneNameProvider, locale, canonicalID);
-                    }
-                    if (names == null) {
-                        // There may be a case that a standard id has become an
-                        // alias.  so, check the aliases backward.
-                        names = examineAliases(timeZoneNameProvider, locale,
-                                   canonicalID == null ? requestID : canonicalID, aliases);
-                    }
-                }
-            }
-
-            if (names != null) {
-                names[0] = requestID;
-            }
-
-            return names;
-        }
-
-        private static String[] examineAliases(TimeZoneNameProvider tznp, Locale locale,
-                                               String id,
-                                               Map<String, String> aliases) {
-            if (aliases.containsValue(id)) {
-                for (Map.Entry<String, String> entry : aliases.entrySet()) {
-                    if (entry.getValue().equals(id)) {
-                        String alias = entry.getKey();
-                        String[] names = buildZoneStrings(tznp, locale, alias);
-                        if (names != null) {
-                            return names;
-                        }
-                        names = examineAliases(tznp, locale, alias, aliases);
-                        if (names != null) {
-                            return names;
-                        }
-                    }
-                }
-            }
-
-            return null;
-        }
-
-        private static String[] buildZoneStrings(TimeZoneNameProvider tznp,
-                                                 Locale locale, String id) {
-            String[] names = new String[5];
-
-            for (int i = 1; i <= 4; i ++) {
-                names[i] = tznp.getDisplayName(id, i>=3, i%2, locale);
-
-                if (names[i] == null) {
-                    switch (i) {
-                    case 1:
-                        // this id seems not localized by this provider
-                        return null;
-                    case 2:
-                    case 4:
-                        // If the display name for SHORT is not supplied,
-                        // copy the LONG name.
-                        names[i] = names[i-1];
-                        break;
-                    case 3:
-                        // If the display name for DST is not supplied,
-                        // copy the "standard" name.
-                        names[3] = names[1];
-                        break;
-                }
-            }
-            }
-
-            return names;
-        }
-    }
-
     private static class TimeZoneNameGetter
         implements LocaleServiceProviderPool.LocalizedObjectGetter<TimeZoneNameProvider,
                                                                    String> {
@@ -299,18 +216,16 @@ public final class TimeZoneNameUtility {
         private static String examineAliases(TimeZoneNameProvider tznp, Locale locale,
                                              String requestID, String tzid, int style,
                                              Map<String, String> aliases) {
-            if (aliases.containsValue(tzid)) {
+            for (Map.Entry<String, String> entry : aliases.entrySet()) {
-                for (Map.Entry<String, String> entry : aliases.entrySet()) {
+                if (entry.getValue().equals(tzid)) {
-                    if (entry.getValue().equals(tzid)) {
+                    String alias = entry.getKey();
-                        String alias = entry.getKey();
+                    String name = getName(tznp, locale, requestID, style, alias);
-                        String name = getName(tznp, locale, requestID, style, alias);
+                    if (name != null) {
-                        if (name != null) {
+                        return name;
-                            return name;
+                    }
-                        }
+                    name = examineAliases(tznp, locale, requestID, alias, style, aliases);
-                        name = examineAliases(tznp, locale, requestID, alias, style, aliases);
+                    if (name != null) {
-                        if (name != null) {
+                        return name;
-                            return name;
-                        }
                     }
                 }
             }

jdk/src/java.base/share/classes/sun/util/resources/TimeZoneNamesBundle.java

@@ -44,6 +44,7 @@ import java.util.Map;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.MissingResourceException;
+import java.util.Objects;
 import java.util.Set;
 
 /**
@@ -60,26 +61,6 @@ import java.util.Set;
  */
 public abstract class TimeZoneNamesBundle extends OpenListResourceBundle {
 
-    /**
-     * Returns a String array containing time zone names. The String array has
-     * at most size elements.
-     *
-     * @param key  the time zone ID for which names are obtained
-     * @param size the requested size of array for names
-     * @return a String array containing names
-     */
-    public String[] getStringArray(String key, int size) {
-        String[] names = handleGetObject(key, size);
-        if ((names == null || names.length != size) && parent != null) {
-            names = ((TimeZoneNamesBundle)parent).getStringArray(key, size);
-        }
-        if (names == null) {
-            throw new MissingResourceException("no time zone names", getClass().getName(), key);
-        }
-        return names;
-
-    }
-
     /**
      * Maps time zone IDs to locale-specific names.
      * The value returned is an array of five strings:
@@ -89,6 +70,8 @@ public abstract class TimeZoneNamesBundle extends OpenListResourceBundle {
      * <li>The short name of the time zone in standard time (localized).
      * <li>The long name of the time zone in daylight savings time (localized).
      * <li>The short name of the time zone in daylight savings time (localized).
+     * <li>The long name of the time zone in generic form (localized).
+     * <li>The short name of the time zone in generic form (localized).
      * </ul>
      * The localized names come from the subclasses's
      * <code>getContents</code> implementations, while the time zone
@@ -96,16 +79,12 @@ public abstract class TimeZoneNamesBundle extends OpenListResourceBundle {
      */
     @Override
     public Object handleGetObject(String key) {
-        return handleGetObject(key, 5);
-    }
-
-    private String[] handleGetObject(String key, int n) {
         String[] contents = (String[]) super.handleGetObject(key);
-        if (contents == null) {
+        if (Objects.isNull(contents)) {
             return null;
         }
-        int clen = Math.min(n - 1, contents.length);
+        int clen = contents.length;
-        String[] tmpobj = new String[clen+1];
+        String[] tmpobj = new String[7];
         tmpobj[0] = key;
         System.arraycopy(contents, 0, tmpobj, 1, clen);
         return tmpobj;

jdk/src/java.base/share/classes/sun/util/resources/en/TimeZoneNames_en_IE.java

@@ -47,7 +47,8 @@ public final class TimeZoneNames_en_IE extends TimeZoneNamesBundle {
     protected final Object[][] getContents() {
         return new Object[][] {
             {"Europe/London", new String[] {"Greenwich Mean Time", "GMT",
-                                    "Irish Summer Time", "IST" /*Dublin*/}},
+                                    "Irish Summer Time", "IST", /*Dublin*/
+                                    "Irish Time", "IT" /*Dublin*/}},
         };
     }
 }

jdk/test/java/util/PluggableLocale/TimeZoneNameProviderTest.java

@@ -25,6 +25,7 @@
  */
 
 import java.text.*;
+import java.time.format.TextStyle;
 import java.util.*;
 import sun.util.locale.provider.*;
 import sun.util.resources.*;
@@ -42,6 +43,7 @@ public class TimeZoneNameProviderTest extends ProviderTest {
         test2();
         test3();
         aliasTest();
+        genericFallbackTest();
     }
 
     void test1() {
@@ -169,9 +171,9 @@ public class TimeZoneNameProviderTest extends ProviderTest {
             for (int style : new int[] { TimeZone.LONG, TimeZone.SHORT }) {
                 String osakaStd = tz.getDisplayName(false, style, OSAKA);
                 if (osakaStd != null) {
-                    // No API for getting generic time zone names
+                    String generic = tz.toZoneId().getDisplayName(
-                    String generic = TimeZoneNameUtility.retrieveGenericDisplayName(tzname,
+                            style == TimeZone.LONG ? TextStyle.FULL : TextStyle.SHORT,
-                                                                                    style, GENERIC);
+                            GENERIC);
                     String expected = "Generic " + osakaStd;
                     if (!expected.equals(generic)) {
                         throw new RuntimeException("Wrong generic name: got=\"" + generic
@@ -230,4 +232,20 @@ public class TimeZoneNameProviderTest extends ProviderTest {
             throw new RuntimeException("Provider's localized name is not available for an alias ID: "+JAPAN+".  result: "+japan+" expected: "+JST_IN_OSAKA);
         }
     }
+
+    /*
+     * Tests whether generic names can be retrieved through fallback.
+     * The test assumes the provider impl for OSAKA locale does NOT
+     * provide generic names.
+     */
+    final String PT = "PT"; // SHORT generic name for "America/Los_Angeles"
+    void genericFallbackTest() {
+        String generic =
+            TimeZone.getTimeZone(LATIME)
+                .toZoneId()
+                .getDisplayName(TextStyle.SHORT, OSAKA);
+        if (!PT.equals(generic)) {
+            throw new RuntimeException("Generic name fallback failed. got: "+generic);
+        }
+    }
 }