669 lines
30 KiB
Java
669 lines
30 KiB
Java
/*
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* Copyright (c) 2008, 2025, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Oracle designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package java.lang.invoke;
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import jdk.internal.misc.VM;
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import jdk.internal.ref.CleanerFactory;
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import sun.invoke.util.Wrapper;
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import java.lang.invoke.MethodHandles.Lookup;
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import java.lang.reflect.Field;
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import static java.lang.invoke.MethodHandleNatives.Constants.*;
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import static java.lang.invoke.MethodHandleStatics.TRACE_METHOD_LINKAGE;
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import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP;
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/**
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* The JVM interface for the method handles package is all here.
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* This is an interface internal and private to an implementation of JSR 292.
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* <em>This class is not part of the JSR 292 standard.</em>
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* @author jrose
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*/
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class MethodHandleNatives {
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private MethodHandleNatives() { } // static only
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//--- MemberName support
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static native void init(MemberName self, Object ref);
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static native void expand(MemberName self);
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static native MemberName resolve(MemberName self, Class<?> caller, int lookupMode,
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boolean speculativeResolve) throws LinkageError, ClassNotFoundException;
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//--- Field layout queries parallel to jdk.internal.misc.Unsafe:
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static native long objectFieldOffset(MemberName self); // e.g., returns vmindex
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static native long staticFieldOffset(MemberName self); // e.g., returns vmindex
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static native Object staticFieldBase(MemberName self); // e.g., returns clazz
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static native Object getMemberVMInfo(MemberName self); // returns {vmindex,vmtarget}
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//--- CallSite support
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/** Tell the JVM that we need to change the target of a CallSite. */
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static native void setCallSiteTargetNormal(CallSite site, MethodHandle target);
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static native void setCallSiteTargetVolatile(CallSite site, MethodHandle target);
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static native void copyOutBootstrapArguments(Class<?> caller, int[] indexInfo,
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int start, int end,
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Object[] buf, int pos,
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boolean resolve,
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Object ifNotAvailable);
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private static native void registerNatives();
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static {
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registerNatives();
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}
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/**
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* Compile-time constants go here. This collection exists not only for
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* reference from clients, but also for ensuring the VM and JDK agree on the
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* values of these constants (see {@link #verifyConstants()}).
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*/
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static class Constants {
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Constants() { } // static only
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static final int
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MN_IS_METHOD = 0x00010000, // method (not constructor)
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MN_IS_CONSTRUCTOR = 0x00020000, // constructor
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MN_IS_FIELD = 0x00040000, // field
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MN_IS_TYPE = 0x00080000, // nested type
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MN_CALLER_SENSITIVE = 0x00100000, // @CallerSensitive annotation detected
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MN_TRUSTED_FINAL = 0x00200000, // trusted final field
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MN_HIDDEN_MEMBER = 0x00400000, // members defined in a hidden class or with @Hidden
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MN_REFERENCE_KIND_SHIFT = 24, // refKind
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MN_REFERENCE_KIND_MASK = 0x0F000000 >> MN_REFERENCE_KIND_SHIFT;
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/**
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* Constant pool reference-kind codes, as used by CONSTANT_MethodHandle CP entries.
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*/
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static final byte
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REF_NONE = 0, // null value
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REF_getField = 1,
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REF_getStatic = 2,
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REF_putField = 3,
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REF_putStatic = 4,
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REF_invokeVirtual = 5,
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REF_invokeStatic = 6,
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REF_invokeSpecial = 7,
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REF_newInvokeSpecial = 8,
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REF_invokeInterface = 9,
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REF_LIMIT = 10;
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/**
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* Flags for Lookup.ClassOptions
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*/
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static final int
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NESTMATE_CLASS = 0x00000001,
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HIDDEN_CLASS = 0x00000002,
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STRONG_LOADER_LINK = 0x00000004,
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ACCESS_VM_ANNOTATIONS = 0x00000008;
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/**
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* Lookup modes
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*/
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static final int
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LM_MODULE = Lookup.MODULE,
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LM_UNCONDITIONAL = Lookup.UNCONDITIONAL,
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LM_TRUSTED = -1;
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}
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static boolean refKindIsValid(int refKind) {
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return (refKind > REF_NONE && refKind < REF_LIMIT);
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}
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static boolean refKindIsField(byte refKind) {
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assert(refKindIsValid(refKind));
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return (refKind <= REF_putStatic);
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}
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static boolean refKindIsGetter(byte refKind) {
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assert(refKindIsValid(refKind));
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return (refKind <= REF_getStatic);
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}
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static boolean refKindIsSetter(byte refKind) {
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return refKindIsField(refKind) && !refKindIsGetter(refKind);
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}
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static boolean refKindIsMethod(byte refKind) {
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return !refKindIsField(refKind) && (refKind != REF_newInvokeSpecial);
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}
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static boolean refKindIsConstructor(byte refKind) {
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return (refKind == REF_newInvokeSpecial);
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}
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static boolean refKindHasReceiver(byte refKind) {
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assert(refKindIsValid(refKind));
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return (refKind & 1) != 0;
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}
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static boolean refKindIsStatic(byte refKind) {
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return !refKindHasReceiver(refKind) && (refKind != REF_newInvokeSpecial);
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}
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static boolean refKindDoesDispatch(byte refKind) {
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assert(refKindIsValid(refKind));
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return (refKind == REF_invokeVirtual ||
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refKind == REF_invokeInterface);
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}
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static {
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final int HR_MASK = ((1 << REF_getField) |
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(1 << REF_putField) |
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(1 << REF_invokeVirtual) |
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(1 << REF_invokeSpecial) |
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(1 << REF_invokeInterface)
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);
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for (byte refKind = REF_NONE+1; refKind < REF_LIMIT; refKind++) {
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assert(refKindHasReceiver(refKind) == (((1<<refKind) & HR_MASK) != 0)) : refKind;
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}
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}
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static String refKindName(byte refKind) {
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assert(refKindIsValid(refKind));
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return switch (refKind) {
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case REF_getField -> "getField";
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case REF_getStatic -> "getStatic";
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case REF_putField -> "putField";
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case REF_putStatic -> "putStatic";
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case REF_invokeVirtual -> "invokeVirtual";
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case REF_invokeStatic -> "invokeStatic";
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case REF_invokeSpecial -> "invokeSpecial";
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case REF_newInvokeSpecial -> "newInvokeSpecial";
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case REF_invokeInterface -> "invokeInterface";
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default -> "REF_???";
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};
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}
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private static native int getNamedCon(int which, Object[] name);
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static boolean verifyConstants() {
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Object[] box = { null };
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for (int i = 0; ; i++) {
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box[0] = null;
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int vmval = getNamedCon(i, box);
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if (box[0] == null) break;
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String name = (String) box[0];
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try {
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Field con = Constants.class.getDeclaredField(name);
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int jval = con.getInt(null);
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if (jval == vmval) continue;
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String err = (name+": JVM has "+vmval+" while Java has "+jval);
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if (name.equals("CONV_OP_LIMIT")) {
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System.err.println("warning: "+err);
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continue;
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}
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throw new InternalError(err);
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} catch (NoSuchFieldException | IllegalAccessException ex) {
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String err = (name+": JVM has "+vmval+" which Java does not define");
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// ignore exotic ops the JVM cares about; we just won't issue them
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//System.err.println("warning: "+err);
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continue;
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}
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}
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return true;
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}
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static {
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VM.setJavaLangInvokeInited();
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assert(verifyConstants());
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}
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// Up-calls from the JVM.
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// These must NOT be public.
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/**
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* The JVM is linking an invokedynamic instruction. Create a reified call site for it.
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*/
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static MemberName linkCallSite(Object callerObj,
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Object bootstrapMethodObj,
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Object nameObj, Object typeObj,
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Object staticArguments,
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Object[] appendixResult) {
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MethodHandle bootstrapMethod = (MethodHandle)bootstrapMethodObj;
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Class<?> caller = (Class<?>)callerObj;
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String name = nameObj.toString().intern();
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MethodType type = (MethodType)typeObj;
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if (!TRACE_METHOD_LINKAGE)
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return linkCallSiteImpl(caller, bootstrapMethod, name, type,
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staticArguments, appendixResult);
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return linkCallSiteTracing(caller, bootstrapMethod, name, type,
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staticArguments, appendixResult);
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}
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static MemberName linkCallSiteImpl(Class<?> caller,
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MethodHandle bootstrapMethod,
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String name, MethodType type,
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Object staticArguments,
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Object[] appendixResult) {
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CallSite callSite = CallSite.makeSite(bootstrapMethod,
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name,
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type,
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staticArguments,
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caller);
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if (TRACE_METHOD_LINKAGE) {
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MethodHandle target = callSite.getTarget();
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System.out.println("linkCallSite target class => " + target.getClass().getName());
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System.out.println("linkCallSite target => " + target.debugString(0));
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}
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if (callSite instanceof ConstantCallSite) {
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appendixResult[0] = callSite.dynamicInvoker();
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return Invokers.linkToTargetMethod(type);
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} else {
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appendixResult[0] = callSite;
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return Invokers.linkToCallSiteMethod(type);
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}
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}
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// Tracing logic:
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static MemberName linkCallSiteTracing(Class<?> caller,
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MethodHandle bootstrapMethod,
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String name, MethodType type,
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Object staticArguments,
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Object[] appendixResult) {
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Object bsmReference = bootstrapMethod.internalMemberName();
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if (bsmReference == null) bsmReference = bootstrapMethod;
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String staticArglist = staticArglistForTrace(staticArguments);
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System.out.println("linkCallSite "+getCallerInfo(caller)+" "+
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bsmReference+" "+
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name+type+"/"+staticArglist);
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try {
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MemberName res = linkCallSiteImpl(caller, bootstrapMethod, name, type,
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staticArguments, appendixResult);
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System.out.println("linkCallSite linkage => "+res+" + "+appendixResult[0]);
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return res;
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} catch (Throwable ex) {
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ex.printStackTrace(); // print now in case exception is swallowed
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System.out.println("linkCallSite => throw "+ex);
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throw ex;
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}
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}
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/**
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* Return a human-readable description of the caller. Something like
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* "java.base/java.security.Security.<clinit>(Security.java:82)"
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*/
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private static String getCallerInfo(Class<?> caller) {
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for (StackTraceElement e : Thread.currentThread().getStackTrace()) {
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if (e.getClassName().equals(caller.getName())) {
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return e.toString();
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}
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}
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// fallback if the caller is somehow missing from the stack.
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return caller.getName();
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}
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// this implements the upcall from the JVM, MethodHandleNatives.linkDynamicConstant:
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static Object linkDynamicConstant(Object callerObj,
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Object bootstrapMethodObj,
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Object nameObj, Object typeObj,
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Object staticArguments) {
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MethodHandle bootstrapMethod = (MethodHandle)bootstrapMethodObj;
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Class<?> caller = (Class<?>)callerObj;
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String name = nameObj.toString().intern();
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Class<?> type = (Class<?>)typeObj;
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if (!TRACE_METHOD_LINKAGE)
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return linkDynamicConstantImpl(caller, bootstrapMethod, name, type, staticArguments);
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return linkDynamicConstantTracing(caller, bootstrapMethod, name, type, staticArguments);
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}
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static Object linkDynamicConstantImpl(Class<?> caller,
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MethodHandle bootstrapMethod,
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String name, Class<?> type,
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Object staticArguments) {
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return ConstantBootstraps.makeConstant(bootstrapMethod, name, type, staticArguments, caller);
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}
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private static String staticArglistForTrace(Object staticArguments) {
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if (staticArguments instanceof Object[] array)
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return "BSA="+java.util.Arrays.asList(array);
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if (staticArguments instanceof int[] array)
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return "BSA@"+java.util.Arrays.toString(array);
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if (staticArguments == null)
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return "BSA0=null";
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return "BSA1="+staticArguments;
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}
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// Tracing logic:
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static Object linkDynamicConstantTracing(Class<?> caller,
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MethodHandle bootstrapMethod,
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String name, Class<?> type,
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Object staticArguments) {
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Object bsmReference = bootstrapMethod.internalMemberName();
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if (bsmReference == null) bsmReference = bootstrapMethod;
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String staticArglist = staticArglistForTrace(staticArguments);
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System.out.println("linkDynamicConstant "+caller.getName()+" "+
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bsmReference+" "+
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name+type+"/"+staticArglist);
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try {
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Object res = linkDynamicConstantImpl(caller, bootstrapMethod, name, type, staticArguments);
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System.out.println("linkDynamicConstantImpl => "+res);
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return res;
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} catch (Throwable ex) {
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ex.printStackTrace(); // print now in case exception is swallowed
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System.out.println("linkDynamicConstant => throw "+ex);
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throw ex;
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}
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}
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/** The JVM is requesting pull-mode bootstrap when it provides
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* a tuple of the form int[]{ argc, vmindex }.
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* The BSM is expected to call back to the JVM using the caller
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* class and vmindex to resolve the static arguments.
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*/
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static boolean staticArgumentsPulled(Object staticArguments) {
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return staticArguments instanceof int[];
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}
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/** A BSM runs in pull-mode if and only if its sole arguments
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* are (Lookup, BootstrapCallInfo), or can be converted pairwise
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* to those types, and it is not of variable arity.
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* Excluding error cases, we can just test that the arity is a constant 2.
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*
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* NOTE: This method currently returns false, since pulling is not currently
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* exposed to a BSM. When pull mode is supported the method block will be
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* replaced with currently commented out code.
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*/
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static boolean isPullModeBSM(MethodHandle bsm) {
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return false;
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// return bsm.type().parameterCount() == 2 && !bsm.isVarargsCollector();
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}
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/**
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* The JVM wants a pointer to a MethodType. Oblige it by finding or creating one.
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*/
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static MethodType findMethodHandleType(Class<?> rtype, Class<?>[] ptypes) {
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return MethodType.methodType(rtype, ptypes, true);
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}
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/**
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* The JVM wants to link a call site that requires a dynamic type check.
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* Name is a type-checking invoker, invokeExact or invoke.
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* Return a JVM method (MemberName) to handle the invoking.
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* The method assumes the following arguments on the stack:
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* 0: the method handle being invoked
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* 1-N: the arguments to the method handle invocation
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* N+1: an optional, implicitly added argument (typically the given MethodType)
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* <p>
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* The nominal method at such a call site is an instance of
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* a signature-polymorphic method (see @PolymorphicSignature).
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* Such method instances are user-visible entities which are
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* "split" from the generic placeholder method in {@code MethodHandle}.
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* (Note that the placeholder method is not identical with any of
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* its instances. If invoked reflectively, is guaranteed to throw an
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* {@code UnsupportedOperationException}.)
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* If the signature-polymorphic method instance is ever reified,
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* it appears as a "copy" of the original placeholder
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* (a native final member of {@code MethodHandle}) except
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* that its type descriptor has shape required by the instance,
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* and the method instance is <em>not</em> varargs.
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* The method instance is also marked synthetic, since the
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* method (by definition) does not appear in Java source code.
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* <p>
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* The JVM is allowed to reify this method as instance metadata.
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* For example, {@code invokeBasic} is always reified.
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* But the JVM may instead call {@code linkMethod}.
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* If the result is an * ordered pair of a {@code (method, appendix)},
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* the method gets all the arguments (0..N inclusive)
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* plus the appendix (N+1), and uses the appendix to complete the call.
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* In this way, one reusable method (called a "linker method")
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* can perform the function of any number of polymorphic instance
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* methods.
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* <p>
|
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* Linker methods are allowed to be weakly typed, with any or
|
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* all references rewritten to {@code Object} and any primitives
|
|
* (except {@code long}/{@code float}/{@code double})
|
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* rewritten to {@code int}.
|
|
* A linker method is trusted to return a strongly typed result,
|
|
* according to the specific method type descriptor of the
|
|
* signature-polymorphic instance it is emulating.
|
|
* This can involve (as necessary) a dynamic check using
|
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* data extracted from the appendix argument.
|
|
* <p>
|
|
* The JVM does not inspect the appendix, other than to pass
|
|
* it verbatim to the linker method at every call.
|
|
* This means that the JDK runtime has wide latitude
|
|
* for choosing the shape of each linker method and its
|
|
* corresponding appendix.
|
|
* Linker methods should be generated from {@code LambdaForm}s
|
|
* so that they do not become visible on stack traces.
|
|
* <p>
|
|
* The {@code linkMethod} call is free to omit the appendix
|
|
* (returning null) and instead emulate the required function
|
|
* completely in the linker method.
|
|
* As a corner case, if N==255, no appendix is possible.
|
|
* In this case, the method returned must be custom-generated to
|
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* perform any needed type checking.
|
|
* <p>
|
|
* If the JVM does not reify a method at a call site, but instead
|
|
* calls {@code linkMethod}, the corresponding call represented
|
|
* in the bytecodes may mention a valid method which is not
|
|
* representable with a {@code MemberName}.
|
|
* Therefore, use cases for {@code linkMethod} tend to correspond to
|
|
* special cases in reflective code such as {@code findVirtual}
|
|
* or {@code revealDirect}.
|
|
*/
|
|
static MemberName linkMethod(Class<?> callerClass, int refKind,
|
|
Class<?> defc, String name, Object type,
|
|
Object[] appendixResult) {
|
|
if (!TRACE_METHOD_LINKAGE)
|
|
return linkMethodImpl(callerClass, refKind, defc, name, type, appendixResult);
|
|
return linkMethodTracing(callerClass, refKind, defc, name, type, appendixResult);
|
|
}
|
|
static MemberName linkMethodImpl(Class<?> callerClass, int refKind,
|
|
Class<?> defc, String name, Object type,
|
|
Object[] appendixResult) {
|
|
try {
|
|
if (refKind == REF_invokeVirtual) {
|
|
if (defc == MethodHandle.class) {
|
|
return Invokers.methodHandleInvokeLinkerMethod(
|
|
name, fixMethodType(callerClass, type), appendixResult);
|
|
} else if (defc == VarHandle.class) {
|
|
return varHandleOperationLinkerMethod(
|
|
name, fixMethodType(callerClass, type), appendixResult);
|
|
}
|
|
}
|
|
} catch (Error e) {
|
|
// Pass through an Error, including say StackOverflowError or
|
|
// OutOfMemoryError
|
|
throw e;
|
|
} catch (Throwable ex) {
|
|
// Wrap anything else in LinkageError
|
|
throw new LinkageError(ex.getMessage(), ex);
|
|
}
|
|
throw new LinkageError("no such method "+defc.getName()+"."+name+type);
|
|
}
|
|
private static MethodType fixMethodType(Class<?> callerClass, Object type) {
|
|
if (type instanceof MethodType mt)
|
|
return mt;
|
|
else
|
|
return MethodType.fromDescriptor((String)type, callerClass.getClassLoader());
|
|
}
|
|
// Tracing logic:
|
|
static MemberName linkMethodTracing(Class<?> callerClass, int refKind,
|
|
Class<?> defc, String name, Object type,
|
|
Object[] appendixResult) {
|
|
System.out.println("linkMethod "+defc.getName()+"."+
|
|
name+type+"/"+Integer.toHexString(refKind));
|
|
try {
|
|
MemberName res = linkMethodImpl(callerClass, refKind, defc, name, type, appendixResult);
|
|
System.out.println("linkMethod => "+res+" + "+appendixResult[0]);
|
|
return res;
|
|
} catch (Throwable ex) {
|
|
System.out.println("linkMethod => throw "+ex);
|
|
throw ex;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Obtain the method to link to the VarHandle operation.
|
|
* This method is located here and not in Invokers to avoid
|
|
* initializing that and other classes early on in VM bootup.
|
|
*/
|
|
private static MemberName varHandleOperationLinkerMethod(String name,
|
|
MethodType mtype,
|
|
Object[] appendixResult) {
|
|
// Get the signature method type
|
|
final MethodType sigType = mtype.basicType();
|
|
|
|
// Get the access kind from the method name
|
|
VarHandle.AccessMode ak;
|
|
try {
|
|
ak = VarHandle.AccessMode.valueFromMethodName(name);
|
|
} catch (IllegalArgumentException e) {
|
|
throw MethodHandleStatics.newInternalError(e);
|
|
}
|
|
|
|
// Create the appendix descriptor constant
|
|
VarHandle.AccessDescriptor ad = new VarHandle.AccessDescriptor(mtype, ak.at.ordinal(), ak.ordinal());
|
|
appendixResult[0] = ad;
|
|
|
|
if (MethodHandleStatics.VAR_HANDLE_GUARDS) {
|
|
// If not polymorphic in the return type, such as the compareAndSet
|
|
// methods that return boolean
|
|
Class<?> guardReturnType = sigType.returnType();
|
|
if (ak.at.isMonomorphicInReturnType) {
|
|
if (ak.at.returnType != mtype.returnType()) {
|
|
// The caller contains a different return type than that
|
|
// defined by the method
|
|
throw newNoSuchMethodErrorOnVarHandle(name, mtype);
|
|
}
|
|
// Adjust the return type of the signature method type
|
|
guardReturnType = ak.at.returnType;
|
|
}
|
|
|
|
// Get the guard method type for linking
|
|
final Class<?>[] guardParams = new Class<?>[sigType.parameterCount() + 2];
|
|
// VarHandle at start
|
|
guardParams[0] = VarHandle.class;
|
|
for (int i = 0; i < sigType.parameterCount(); i++) {
|
|
guardParams[i + 1] = sigType.parameterType(i);
|
|
}
|
|
// Access descriptor at end
|
|
guardParams[guardParams.length - 1] = VarHandle.AccessDescriptor.class;
|
|
MethodType guardType = MethodType.methodType(guardReturnType, guardParams, true);
|
|
|
|
MemberName linker = new MemberName(
|
|
VarHandleGuards.class, getVarHandleGuardMethodName(guardType),
|
|
guardType, REF_invokeStatic);
|
|
|
|
linker = MemberName.getFactory().resolveOrNull(REF_invokeStatic, linker,
|
|
VarHandleGuards.class, LM_TRUSTED);
|
|
if (linker != null) {
|
|
return linker;
|
|
}
|
|
// Fall back to lambda form linkage if guard method is not available
|
|
// TODO Optionally log fallback ?
|
|
}
|
|
return Invokers.varHandleInvokeLinkerMethod(mtype);
|
|
}
|
|
static String getVarHandleGuardMethodName(MethodType guardType) {
|
|
String prefix = "guard_";
|
|
StringBuilder sb = new StringBuilder(prefix.length() + guardType.parameterCount());
|
|
|
|
sb.append(prefix);
|
|
for (int i = 1; i < guardType.parameterCount() - 1; i++) {
|
|
Class<?> pt = guardType.parameterType(i);
|
|
sb.append(getCharType(pt));
|
|
}
|
|
sb.append('_').append(getCharType(guardType.returnType()));
|
|
return sb.toString();
|
|
}
|
|
static char getCharType(Class<?> pt) {
|
|
return Wrapper.forBasicType(pt).basicTypeChar();
|
|
}
|
|
static NoSuchMethodError newNoSuchMethodErrorOnVarHandle(String name, MethodType mtype) {
|
|
return new NoSuchMethodError("VarHandle." + name + mtype);
|
|
}
|
|
|
|
/**
|
|
* The JVM is resolving a CONSTANT_MethodHandle CP entry. And it wants our help.
|
|
* It will make an up-call to this method. (Do not change the name or signature.)
|
|
* The type argument is a Class for field requests and a MethodType for non-fields.
|
|
* <p>
|
|
* Recent versions of the JVM may also pass a resolved MemberName for the type.
|
|
* In that case, the name is ignored and may be null.
|
|
*/
|
|
static MethodHandle linkMethodHandleConstant(Class<?> callerClass, int refKind,
|
|
Class<?> defc, String name, Object type) {
|
|
try {
|
|
Lookup lookup = IMPL_LOOKUP.in(callerClass);
|
|
assert(refKindIsValid(refKind));
|
|
return lookup.linkMethodHandleConstant((byte) refKind, defc, name, type);
|
|
} catch (ReflectiveOperationException ex) {
|
|
throw mapLookupExceptionToError(ex);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Map a reflective exception to a linkage error.
|
|
*/
|
|
static LinkageError mapLookupExceptionToError(ReflectiveOperationException ex) {
|
|
LinkageError err;
|
|
if (ex instanceof IllegalAccessException) {
|
|
Throwable cause = ex.getCause();
|
|
if (cause instanceof AbstractMethodError ame) {
|
|
return ame;
|
|
} else {
|
|
err = new IllegalAccessError(ex.getMessage());
|
|
}
|
|
} else if (ex instanceof NoSuchMethodException) {
|
|
err = new NoSuchMethodError(ex.getMessage());
|
|
} else if (ex instanceof NoSuchFieldException) {
|
|
err = new NoSuchFieldError(ex.getMessage());
|
|
} else {
|
|
err = new IncompatibleClassChangeError();
|
|
}
|
|
return initCauseFrom(err, ex);
|
|
}
|
|
|
|
/**
|
|
* Use best possible cause for err.initCause(), substituting the
|
|
* cause for err itself if the cause has the same (or better) type.
|
|
*/
|
|
static <E extends Error> E initCauseFrom(E err, Exception ex) {
|
|
Throwable th = ex.getCause();
|
|
@SuppressWarnings("unchecked")
|
|
final Class<E> Eclass = (Class<E>) err.getClass();
|
|
if (Eclass.isInstance(th))
|
|
return Eclass.cast(th);
|
|
err.initCause(th == null ? ex : th);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* Is this method a caller-sensitive method?
|
|
* I.e., does it call Reflection.getCallerClass or a similar method
|
|
* to ask about the identity of its caller?
|
|
*/
|
|
static boolean isCallerSensitive(MemberName mem) {
|
|
if (!mem.isInvocable()) return false; // fields are not caller sensitive
|
|
|
|
return mem.isCallerSensitive() || canBeCalledVirtual(mem);
|
|
}
|
|
|
|
static boolean canBeCalledVirtual(MemberName mem) {
|
|
assert(mem.isInvocable());
|
|
return mem.getName().equals("getContextClassLoader") && canBeCalledVirtual(mem, java.lang.Thread.class);
|
|
}
|
|
|
|
static boolean canBeCalledVirtual(MemberName symbolicRef, Class<?> definingClass) {
|
|
Class<?> symbolicRefClass = symbolicRef.getDeclaringClass();
|
|
if (symbolicRefClass == definingClass) return true;
|
|
if (symbolicRef.isStatic() || symbolicRef.isPrivate()) return false;
|
|
return (definingClass.isAssignableFrom(symbolicRefClass) || // Msym overrides Mdef
|
|
symbolicRefClass.isInterface()); // Mdef implements Msym
|
|
}
|
|
}
|