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/*
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* Copyright (c) 2008, 2013, 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 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.*;
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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) throws LinkageError;
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static native int getMembers(Class<?> defc, String matchName, String matchSig,
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int matchFlags, Class<?> caller, int skip, MemberName[] results);
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/// Field layout queries parallel to sun.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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/// MethodHandle support
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/** Fetch MH-related JVM parameter.
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* which=0 retrieves MethodHandlePushLimit
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* which=1 retrieves stack slot push size (in address units)
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*/
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static native int getConstant(int which);
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static final boolean COUNT_GWT;
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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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private static native void registerNatives();
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static {
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registerNatives();
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COUNT_GWT = getConstant(Constants.GC_COUNT_GWT) != 0;
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// The JVM calls MethodHandleNatives.<clinit>. Cascade the <clinit> calls as needed:
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MethodHandleImpl.initStatics();
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}
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// All compile-time constants go here.
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// There is an opportunity to check them against the JVM's idea of them.
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static class Constants {
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Constants() { } // static only
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// MethodHandleImpl
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static final int // for getConstant
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GC_COUNT_GWT = 4,
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GC_LAMBDA_SUPPORT = 5;
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// MemberName
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// The JVM uses values of -2 and above for vtable indexes.
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// Field values are simple positive offsets.
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// Ref: src/share/vm/oops/methodOop.hpp
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// This value is negative enough to avoid such numbers,
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// but not too negative.
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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_REFERENCE_KIND_SHIFT = 24, // refKind
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MN_REFERENCE_KIND_MASK = 0x0F000000 >> MN_REFERENCE_KIND_SHIFT,
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// The SEARCH_* bits are not for MN.flags but for the matchFlags argument of MHN.getMembers:
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MN_SEARCH_SUPERCLASSES = 0x00100000,
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MN_SEARCH_INTERFACES = 0x00200000;
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/**
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* Basic types as encoded in the JVM. These code values are not
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* intended for use outside this class. They are used as part of
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* a private interface between the JVM and this class.
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*/
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static final int
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T_BOOLEAN = 4,
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T_CHAR = 5,
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T_FLOAT = 6,
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T_DOUBLE = 7,
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T_BYTE = 8,
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T_SHORT = 9,
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T_INT = 10,
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T_LONG = 11,
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T_OBJECT = 12,
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//T_ARRAY = 13
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T_VOID = 14,
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//T_ADDRESS = 15
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T_ILLEGAL = 99;
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/**
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* Constant pool entry types.
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*/
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static final byte
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CONSTANT_Utf8 = 1,
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CONSTANT_Integer = 3,
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CONSTANT_Float = 4,
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CONSTANT_Long = 5,
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CONSTANT_Double = 6,
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CONSTANT_Class = 7,
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CONSTANT_String = 8,
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CONSTANT_Fieldref = 9,
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CONSTANT_Methodref = 10,
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CONSTANT_InterfaceMethodref = 11,
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CONSTANT_NameAndType = 12,
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CONSTANT_MethodHandle = 15, // JSR 292
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CONSTANT_MethodType = 16, // JSR 292
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CONSTANT_InvokeDynamic = 18,
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CONSTANT_LIMIT = 19; // Limit to tags found in classfiles
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/**
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* Access modifier flags.
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*/
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static final char
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ACC_PUBLIC = 0x0001,
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ACC_PRIVATE = 0x0002,
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ACC_PROTECTED = 0x0004,
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ACC_STATIC = 0x0008,
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ACC_FINAL = 0x0010,
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ACC_SYNCHRONIZED = 0x0020,
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ACC_VOLATILE = 0x0040,
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ACC_TRANSIENT = 0x0080,
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ACC_NATIVE = 0x0100,
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ACC_INTERFACE = 0x0200,
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ACC_ABSTRACT = 0x0400,
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ACC_STRICT = 0x0800,
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ACC_SYNTHETIC = 0x1000,
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ACC_ANNOTATION = 0x2000,
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ACC_ENUM = 0x4000,
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// aliases:
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ACC_SUPER = ACC_SYNCHRONIZED,
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ACC_BRIDGE = ACC_VOLATILE,
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ACC_VARARGS = ACC_TRANSIENT;
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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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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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switch (refKind) {
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case REF_getField: return "getField";
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case REF_getStatic: return "getStatic";
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case REF_putField: return "putField";
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case REF_putStatic: return "putStatic";
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case REF_invokeVirtual: return "invokeVirtual";
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case REF_invokeStatic: return "invokeStatic";
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case REF_invokeSpecial: return "invokeSpecial";
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case REF_newInvokeSpecial: return "newInvokeSpecial";
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case REF_invokeInterface: return "invokeInterface";
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default: return "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 wont 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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jaroslav@1646
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assert(verifyConstants());
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}
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jaroslav@1646
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jaroslav@1646
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// Up-calls from the JVM.
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// These must NOT be public.
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jaroslav@1646
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/**
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jaroslav@1646
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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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jaroslav@1646
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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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296 |
CallSite callSite = CallSite.makeSite(bootstrapMethod,
|
jaroslav@1646
|
297 |
name,
|
jaroslav@1646
|
298 |
type,
|
jaroslav@1646
|
299 |
staticArguments,
|
jaroslav@1646
|
300 |
caller);
|
jaroslav@1646
|
301 |
if (callSite instanceof ConstantCallSite) {
|
jaroslav@1646
|
302 |
appendixResult[0] = callSite.dynamicInvoker();
|
jaroslav@1646
|
303 |
return Invokers.linkToTargetMethod(type);
|
jaroslav@1646
|
304 |
} else {
|
jaroslav@1646
|
305 |
appendixResult[0] = callSite;
|
jaroslav@1646
|
306 |
return Invokers.linkToCallSiteMethod(type);
|
jaroslav@1646
|
307 |
}
|
jaroslav@1646
|
308 |
}
|
jaroslav@1646
|
309 |
|
jaroslav@1646
|
310 |
/**
|
jaroslav@1646
|
311 |
* The JVM wants a pointer to a MethodType. Oblige it by finding or creating one.
|
jaroslav@1646
|
312 |
*/
|
jaroslav@1646
|
313 |
static MethodType findMethodHandleType(Class<?> rtype, Class<?>[] ptypes) {
|
jaroslav@1646
|
314 |
return MethodType.makeImpl(rtype, ptypes, true);
|
jaroslav@1646
|
315 |
}
|
jaroslav@1646
|
316 |
|
jaroslav@1646
|
317 |
/**
|
jaroslav@1646
|
318 |
* The JVM wants to link a call site that requires a dynamic type check.
|
jaroslav@1646
|
319 |
* Name is a type-checking invoker, invokeExact or invoke.
|
jaroslav@1646
|
320 |
* Return a JVM method (MemberName) to handle the invoking.
|
jaroslav@1646
|
321 |
* The method assumes the following arguments on the stack:
|
jaroslav@1646
|
322 |
* 0: the method handle being invoked
|
jaroslav@1646
|
323 |
* 1-N: the arguments to the method handle invocation
|
jaroslav@1646
|
324 |
* N+1: an optional, implicitly added argument (typically the given MethodType)
|
jaroslav@1646
|
325 |
* <p>
|
jaroslav@1646
|
326 |
* The nominal method at such a call site is an instance of
|
jaroslav@1646
|
327 |
* a signature-polymorphic method (see @PolymorphicSignature).
|
jaroslav@1646
|
328 |
* Such method instances are user-visible entities which are
|
jaroslav@1646
|
329 |
* "split" from the generic placeholder method in {@code MethodHandle}.
|
jaroslav@1646
|
330 |
* (Note that the placeholder method is not identical with any of
|
jaroslav@1646
|
331 |
* its instances. If invoked reflectively, is guaranteed to throw an
|
jaroslav@1646
|
332 |
* {@code UnsupportedOperationException}.)
|
jaroslav@1646
|
333 |
* If the signature-polymorphic method instance is ever reified,
|
jaroslav@1646
|
334 |
* it appears as a "copy" of the original placeholder
|
jaroslav@1646
|
335 |
* (a native final member of {@code MethodHandle}) except
|
jaroslav@1646
|
336 |
* that its type descriptor has shape required by the instance,
|
jaroslav@1646
|
337 |
* and the method instance is <em>not</em> varargs.
|
jaroslav@1646
|
338 |
* The method instance is also marked synthetic, since the
|
jaroslav@1646
|
339 |
* method (by definition) does not appear in Java source code.
|
jaroslav@1646
|
340 |
* <p>
|
jaroslav@1646
|
341 |
* The JVM is allowed to reify this method as instance metadata.
|
jaroslav@1646
|
342 |
* For example, {@code invokeBasic} is always reified.
|
jaroslav@1646
|
343 |
* But the JVM may instead call {@code linkMethod}.
|
jaroslav@1646
|
344 |
* If the result is an * ordered pair of a {@code (method, appendix)},
|
jaroslav@1646
|
345 |
* the method gets all the arguments (0..N inclusive)
|
jaroslav@1646
|
346 |
* plus the appendix (N+1), and uses the appendix to complete the call.
|
jaroslav@1646
|
347 |
* In this way, one reusable method (called a "linker method")
|
jaroslav@1646
|
348 |
* can perform the function of any number of polymorphic instance
|
jaroslav@1646
|
349 |
* methods.
|
jaroslav@1646
|
350 |
* <p>
|
jaroslav@1646
|
351 |
* Linker methods are allowed to be weakly typed, with any or
|
jaroslav@1646
|
352 |
* all references rewritten to {@code Object} and any primitives
|
jaroslav@1646
|
353 |
* (except {@code long}/{@code float}/{@code double})
|
jaroslav@1646
|
354 |
* rewritten to {@code int}.
|
jaroslav@1646
|
355 |
* A linker method is trusted to return a strongly typed result,
|
jaroslav@1646
|
356 |
* according to the specific method type descriptor of the
|
jaroslav@1646
|
357 |
* signature-polymorphic instance it is emulating.
|
jaroslav@1646
|
358 |
* This can involve (as necessary) a dynamic check using
|
jaroslav@1646
|
359 |
* data extracted from the appendix argument.
|
jaroslav@1646
|
360 |
* <p>
|
jaroslav@1646
|
361 |
* The JVM does not inspect the appendix, other than to pass
|
jaroslav@1646
|
362 |
* it verbatim to the linker method at every call.
|
jaroslav@1646
|
363 |
* This means that the JDK runtime has wide latitude
|
jaroslav@1646
|
364 |
* for choosing the shape of each linker method and its
|
jaroslav@1646
|
365 |
* corresponding appendix.
|
jaroslav@1646
|
366 |
* Linker methods should be generated from {@code LambdaForm}s
|
jaroslav@1646
|
367 |
* so that they do not become visible on stack traces.
|
jaroslav@1646
|
368 |
* <p>
|
jaroslav@1646
|
369 |
* The {@code linkMethod} call is free to omit the appendix
|
jaroslav@1646
|
370 |
* (returning null) and instead emulate the required function
|
jaroslav@1646
|
371 |
* completely in the linker method.
|
jaroslav@1646
|
372 |
* As a corner case, if N==255, no appendix is possible.
|
jaroslav@1646
|
373 |
* In this case, the method returned must be custom-generated to
|
jaroslav@1646
|
374 |
* to perform any needed type checking.
|
jaroslav@1646
|
375 |
* <p>
|
jaroslav@1646
|
376 |
* If the JVM does not reify a method at a call site, but instead
|
jaroslav@1646
|
377 |
* calls {@code linkMethod}, the corresponding call represented
|
jaroslav@1646
|
378 |
* in the bytecodes may mention a valid method which is not
|
jaroslav@1646
|
379 |
* representable with a {@code MemberName}.
|
jaroslav@1646
|
380 |
* Therefore, use cases for {@code linkMethod} tend to correspond to
|
jaroslav@1646
|
381 |
* special cases in reflective code such as {@code findVirtual}
|
jaroslav@1646
|
382 |
* or {@code revealDirect}.
|
jaroslav@1646
|
383 |
*/
|
jaroslav@1646
|
384 |
static MemberName linkMethod(Class<?> callerClass, int refKind,
|
jaroslav@1646
|
385 |
Class<?> defc, String name, Object type,
|
jaroslav@1646
|
386 |
Object[] appendixResult) {
|
jaroslav@1646
|
387 |
if (!TRACE_METHOD_LINKAGE)
|
jaroslav@1646
|
388 |
return linkMethodImpl(callerClass, refKind, defc, name, type, appendixResult);
|
jaroslav@1646
|
389 |
return linkMethodTracing(callerClass, refKind, defc, name, type, appendixResult);
|
jaroslav@1646
|
390 |
}
|
jaroslav@1646
|
391 |
static MemberName linkMethodImpl(Class<?> callerClass, int refKind,
|
jaroslav@1646
|
392 |
Class<?> defc, String name, Object type,
|
jaroslav@1646
|
393 |
Object[] appendixResult) {
|
jaroslav@1646
|
394 |
try {
|
jaroslav@1646
|
395 |
if (defc == MethodHandle.class && refKind == REF_invokeVirtual) {
|
jaroslav@1646
|
396 |
return Invokers.methodHandleInvokeLinkerMethod(name, fixMethodType(callerClass, type), appendixResult);
|
jaroslav@1646
|
397 |
}
|
jaroslav@1646
|
398 |
} catch (Throwable ex) {
|
jaroslav@1646
|
399 |
if (ex instanceof LinkageError)
|
jaroslav@1646
|
400 |
throw (LinkageError) ex;
|
jaroslav@1646
|
401 |
else
|
jaroslav@1646
|
402 |
throw new LinkageError(ex.getMessage(), ex);
|
jaroslav@1646
|
403 |
}
|
jaroslav@1646
|
404 |
throw new LinkageError("no such method "+defc.getName()+"."+name+type);
|
jaroslav@1646
|
405 |
}
|
jaroslav@1646
|
406 |
private static MethodType fixMethodType(Class<?> callerClass, Object type) {
|
jaroslav@1646
|
407 |
if (type instanceof MethodType)
|
jaroslav@1646
|
408 |
return (MethodType) type;
|
jaroslav@1646
|
409 |
else
|
jaroslav@1646
|
410 |
return MethodType.fromMethodDescriptorString((String)type, callerClass.getClassLoader());
|
jaroslav@1646
|
411 |
}
|
jaroslav@1646
|
412 |
// Tracing logic:
|
jaroslav@1646
|
413 |
static MemberName linkMethodTracing(Class<?> callerClass, int refKind,
|
jaroslav@1646
|
414 |
Class<?> defc, String name, Object type,
|
jaroslav@1646
|
415 |
Object[] appendixResult) {
|
jaroslav@1646
|
416 |
System.out.println("linkMethod "+defc.getName()+"."+
|
jaroslav@1646
|
417 |
name+type+"/"+Integer.toHexString(refKind));
|
jaroslav@1646
|
418 |
try {
|
jaroslav@1646
|
419 |
MemberName res = linkMethodImpl(callerClass, refKind, defc, name, type, appendixResult);
|
jaroslav@1646
|
420 |
System.out.println("linkMethod => "+res+" + "+appendixResult[0]);
|
jaroslav@1646
|
421 |
return res;
|
jaroslav@1646
|
422 |
} catch (Throwable ex) {
|
jaroslav@1646
|
423 |
System.out.println("linkMethod => throw "+ex);
|
jaroslav@1646
|
424 |
throw ex;
|
jaroslav@1646
|
425 |
}
|
jaroslav@1646
|
426 |
}
|
jaroslav@1646
|
427 |
|
jaroslav@1646
|
428 |
|
jaroslav@1646
|
429 |
/**
|
jaroslav@1646
|
430 |
* The JVM is resolving a CONSTANT_MethodHandle CP entry. And it wants our help.
|
jaroslav@1646
|
431 |
* It will make an up-call to this method. (Do not change the name or signature.)
|
jaroslav@1646
|
432 |
* The type argument is a Class for field requests and a MethodType for non-fields.
|
jaroslav@1646
|
433 |
* <p>
|
jaroslav@1646
|
434 |
* Recent versions of the JVM may also pass a resolved MemberName for the type.
|
jaroslav@1646
|
435 |
* In that case, the name is ignored and may be null.
|
jaroslav@1646
|
436 |
*/
|
jaroslav@1646
|
437 |
static MethodHandle linkMethodHandleConstant(Class<?> callerClass, int refKind,
|
jaroslav@1646
|
438 |
Class<?> defc, String name, Object type) {
|
jaroslav@1646
|
439 |
try {
|
jaroslav@1646
|
440 |
Lookup lookup = IMPL_LOOKUP.in(callerClass);
|
jaroslav@1646
|
441 |
assert(refKindIsValid(refKind));
|
jaroslav@1646
|
442 |
return lookup.linkMethodHandleConstant((byte) refKind, defc, name, type);
|
jaroslav@1646
|
443 |
} catch (IllegalAccessException ex) {
|
jaroslav@1646
|
444 |
Throwable cause = ex.getCause();
|
jaroslav@1646
|
445 |
if (cause instanceof AbstractMethodError) {
|
jaroslav@1646
|
446 |
throw (AbstractMethodError) cause;
|
jaroslav@1646
|
447 |
} else {
|
jaroslav@1646
|
448 |
Error err = new IllegalAccessError(ex.getMessage());
|
jaroslav@1646
|
449 |
throw initCauseFrom(err, ex);
|
jaroslav@1646
|
450 |
}
|
jaroslav@1646
|
451 |
} catch (NoSuchMethodException ex) {
|
jaroslav@1646
|
452 |
Error err = new NoSuchMethodError(ex.getMessage());
|
jaroslav@1646
|
453 |
throw initCauseFrom(err, ex);
|
jaroslav@1646
|
454 |
} catch (NoSuchFieldException ex) {
|
jaroslav@1646
|
455 |
Error err = new NoSuchFieldError(ex.getMessage());
|
jaroslav@1646
|
456 |
throw initCauseFrom(err, ex);
|
jaroslav@1646
|
457 |
} catch (ReflectiveOperationException ex) {
|
jaroslav@1646
|
458 |
Error err = new IncompatibleClassChangeError();
|
jaroslav@1646
|
459 |
throw initCauseFrom(err, ex);
|
jaroslav@1646
|
460 |
}
|
jaroslav@1646
|
461 |
}
|
jaroslav@1646
|
462 |
|
jaroslav@1646
|
463 |
/**
|
jaroslav@1646
|
464 |
* Use best possible cause for err.initCause(), substituting the
|
jaroslav@1646
|
465 |
* cause for err itself if the cause has the same (or better) type.
|
jaroslav@1646
|
466 |
*/
|
jaroslav@1646
|
467 |
static private Error initCauseFrom(Error err, Exception ex) {
|
jaroslav@1646
|
468 |
Throwable th = ex.getCause();
|
jaroslav@1646
|
469 |
if (err.getClass().isInstance(th))
|
jaroslav@1646
|
470 |
return (Error) th;
|
jaroslav@1646
|
471 |
err.initCause(th == null ? ex : th);
|
jaroslav@1646
|
472 |
return err;
|
jaroslav@1646
|
473 |
}
|
jaroslav@1646
|
474 |
|
jaroslav@1646
|
475 |
/**
|
jaroslav@1646
|
476 |
* Is this method a caller-sensitive method?
|
jaroslav@1646
|
477 |
* I.e., does it call Reflection.getCallerClass or a similer method
|
jaroslav@1646
|
478 |
* to ask about the identity of its caller?
|
jaroslav@1646
|
479 |
*/
|
jaroslav@1646
|
480 |
static boolean isCallerSensitive(MemberName mem) {
|
jaroslav@1646
|
481 |
if (!mem.isInvocable()) return false; // fields are not caller sensitive
|
jaroslav@1646
|
482 |
|
jaroslav@1646
|
483 |
return mem.isCallerSensitive() || canBeCalledVirtual(mem);
|
jaroslav@1646
|
484 |
}
|
jaroslav@1646
|
485 |
|
jaroslav@1646
|
486 |
static boolean canBeCalledVirtual(MemberName mem) {
|
jaroslav@1646
|
487 |
assert(mem.isInvocable());
|
jaroslav@1646
|
488 |
Class<?> defc = mem.getDeclaringClass();
|
jaroslav@1646
|
489 |
switch (mem.getName()) {
|
jaroslav@1646
|
490 |
case "checkMemberAccess":
|
jaroslav@1646
|
491 |
return canBeCalledVirtual(mem, java.lang.SecurityManager.class);
|
jaroslav@1646
|
492 |
case "getContextClassLoader":
|
jaroslav@1646
|
493 |
return canBeCalledVirtual(mem, java.lang.Thread.class);
|
jaroslav@1646
|
494 |
}
|
jaroslav@1646
|
495 |
return false;
|
jaroslav@1646
|
496 |
}
|
jaroslav@1646
|
497 |
|
jaroslav@1646
|
498 |
static boolean canBeCalledVirtual(MemberName symbolicRef, Class<?> definingClass) {
|
jaroslav@1646
|
499 |
Class<?> symbolicRefClass = symbolicRef.getDeclaringClass();
|
jaroslav@1646
|
500 |
if (symbolicRefClass == definingClass) return true;
|
jaroslav@1646
|
501 |
if (symbolicRef.isStatic() || symbolicRef.isPrivate()) return false;
|
jaroslav@1646
|
502 |
return (definingClass.isAssignableFrom(symbolicRefClass) || // Msym overrides Mdef
|
jaroslav@1646
|
503 |
symbolicRefClass.isInterface()); // Mdef implements Msym
|
jaroslav@1646
|
504 |
}
|
jaroslav@1646
|
505 |
}
|