| /* |
| * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.lang.invoke; |
| |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.util.Arrays; |
| import java.util.HashMap; |
| import sun.invoke.empty.Empty; |
| import sun.invoke.util.ValueConversions; |
| import sun.invoke.util.VerifyType; |
| import sun.invoke.util.Wrapper; |
| import sun.reflect.CallerSensitive; |
| import sun.reflect.Reflection; |
| import static java.lang.invoke.LambdaForm.*; |
| import static java.lang.invoke.MethodHandleStatics.*; |
| import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP; |
| |
| /** |
| * Trusted implementation code for MethodHandle. |
| * @author jrose |
| */ |
| /*non-public*/ abstract class MethodHandleImpl { |
| /// Factory methods to create method handles: |
| |
| static void initStatics() { |
| // Trigger selected static initializations. |
| MemberName.Factory.INSTANCE.getClass(); |
| } |
| |
| static MethodHandle makeArrayElementAccessor(Class<?> arrayClass, boolean isSetter) { |
| if (!arrayClass.isArray()) |
| throw newIllegalArgumentException("not an array: "+arrayClass); |
| MethodHandle accessor = ArrayAccessor.getAccessor(arrayClass, isSetter); |
| MethodType srcType = accessor.type().erase(); |
| MethodType lambdaType = srcType.invokerType(); |
| Name[] names = arguments(1, lambdaType); |
| Name[] args = Arrays.copyOfRange(names, 1, 1 + srcType.parameterCount()); |
| names[names.length - 1] = new Name(accessor.asType(srcType), (Object[]) args); |
| LambdaForm form = new LambdaForm("getElement", lambdaType.parameterCount(), names); |
| MethodHandle mh = SimpleMethodHandle.make(srcType, form); |
| if (ArrayAccessor.needCast(arrayClass)) { |
| mh = mh.bindTo(arrayClass); |
| } |
| mh = mh.asType(ArrayAccessor.correctType(arrayClass, isSetter)); |
| return mh; |
| } |
| |
| static final class ArrayAccessor { |
| /// Support for array element access |
| static final HashMap<Class<?>, MethodHandle> GETTER_CACHE = new HashMap<>(); // TODO use it |
| static final HashMap<Class<?>, MethodHandle> SETTER_CACHE = new HashMap<>(); // TODO use it |
| |
| static int getElementI(int[] a, int i) { return a[i]; } |
| static long getElementJ(long[] a, int i) { return a[i]; } |
| static float getElementF(float[] a, int i) { return a[i]; } |
| static double getElementD(double[] a, int i) { return a[i]; } |
| static boolean getElementZ(boolean[] a, int i) { return a[i]; } |
| static byte getElementB(byte[] a, int i) { return a[i]; } |
| static short getElementS(short[] a, int i) { return a[i]; } |
| static char getElementC(char[] a, int i) { return a[i]; } |
| static Object getElementL(Object[] a, int i) { return a[i]; } |
| |
| static void setElementI(int[] a, int i, int x) { a[i] = x; } |
| static void setElementJ(long[] a, int i, long x) { a[i] = x; } |
| static void setElementF(float[] a, int i, float x) { a[i] = x; } |
| static void setElementD(double[] a, int i, double x) { a[i] = x; } |
| static void setElementZ(boolean[] a, int i, boolean x) { a[i] = x; } |
| static void setElementB(byte[] a, int i, byte x) { a[i] = x; } |
| static void setElementS(short[] a, int i, short x) { a[i] = x; } |
| static void setElementC(char[] a, int i, char x) { a[i] = x; } |
| static void setElementL(Object[] a, int i, Object x) { a[i] = x; } |
| |
| static Object getElementL(Class<?> arrayClass, Object[] a, int i) { arrayClass.cast(a); return a[i]; } |
| static void setElementL(Class<?> arrayClass, Object[] a, int i, Object x) { arrayClass.cast(a); a[i] = x; } |
| |
| // Weakly typed wrappers of Object[] accessors: |
| static Object getElementL(Object a, int i) { return getElementL((Object[])a, i); } |
| static void setElementL(Object a, int i, Object x) { setElementL((Object[]) a, i, x); } |
| static Object getElementL(Object arrayClass, Object a, int i) { return getElementL((Class<?>) arrayClass, (Object[])a, i); } |
| static void setElementL(Object arrayClass, Object a, int i, Object x) { setElementL((Class<?>) arrayClass, (Object[])a, i, x); } |
| |
| static boolean needCast(Class<?> arrayClass) { |
| Class<?> elemClass = arrayClass.getComponentType(); |
| return !elemClass.isPrimitive() && elemClass != Object.class; |
| } |
| static String name(Class<?> arrayClass, boolean isSetter) { |
| Class<?> elemClass = arrayClass.getComponentType(); |
| if (elemClass == null) throw new IllegalArgumentException(); |
| return (!isSetter ? "getElement" : "setElement") + Wrapper.basicTypeChar(elemClass); |
| } |
| static final boolean USE_WEAKLY_TYPED_ARRAY_ACCESSORS = false; // FIXME: decide |
| static MethodType type(Class<?> arrayClass, boolean isSetter) { |
| Class<?> elemClass = arrayClass.getComponentType(); |
| Class<?> arrayArgClass = arrayClass; |
| if (!elemClass.isPrimitive()) { |
| arrayArgClass = Object[].class; |
| if (USE_WEAKLY_TYPED_ARRAY_ACCESSORS) |
| arrayArgClass = Object.class; |
| } |
| if (!needCast(arrayClass)) { |
| return !isSetter ? |
| MethodType.methodType(elemClass, arrayArgClass, int.class) : |
| MethodType.methodType(void.class, arrayArgClass, int.class, elemClass); |
| } else { |
| Class<?> classArgClass = Class.class; |
| if (USE_WEAKLY_TYPED_ARRAY_ACCESSORS) |
| classArgClass = Object.class; |
| return !isSetter ? |
| MethodType.methodType(Object.class, classArgClass, arrayArgClass, int.class) : |
| MethodType.methodType(void.class, classArgClass, arrayArgClass, int.class, Object.class); |
| } |
| } |
| static MethodType correctType(Class<?> arrayClass, boolean isSetter) { |
| Class<?> elemClass = arrayClass.getComponentType(); |
| return !isSetter ? |
| MethodType.methodType(elemClass, arrayClass, int.class) : |
| MethodType.methodType(void.class, arrayClass, int.class, elemClass); |
| } |
| static MethodHandle getAccessor(Class<?> arrayClass, boolean isSetter) { |
| String name = name(arrayClass, isSetter); |
| MethodType type = type(arrayClass, isSetter); |
| try { |
| return IMPL_LOOKUP.findStatic(ArrayAccessor.class, name, type); |
| } catch (ReflectiveOperationException ex) { |
| throw uncaughtException(ex); |
| } |
| } |
| } |
| |
| /** |
| * Create a JVM-level adapter method handle to conform the given method |
| * handle to the similar newType, using only pairwise argument conversions. |
| * For each argument, convert incoming argument to the exact type needed. |
| * The argument conversions allowed are casting, boxing and unboxing, |
| * integral widening or narrowing, and floating point widening or narrowing. |
| * @param srcType required call type |
| * @param target original method handle |
| * @param level which strength of conversion is allowed |
| * @return an adapter to the original handle with the desired new type, |
| * or the original target if the types are already identical |
| * or null if the adaptation cannot be made |
| */ |
| static MethodHandle makePairwiseConvert(MethodHandle target, MethodType srcType, int level) { |
| assert(level >= 0 && level <= 2); |
| MethodType dstType = target.type(); |
| assert(dstType.parameterCount() == target.type().parameterCount()); |
| if (srcType == dstType) |
| return target; |
| |
| // Calculate extra arguments (temporaries) required in the names array. |
| // FIXME: Use an ArrayList<Name>. Some arguments require more than one conversion step. |
| final int INARG_COUNT = srcType.parameterCount(); |
| int conversions = 0; |
| boolean[] needConv = new boolean[1+INARG_COUNT]; |
| for (int i = 0; i <= INARG_COUNT; i++) { |
| Class<?> src = (i == INARG_COUNT) ? dstType.returnType() : srcType.parameterType(i); |
| Class<?> dst = (i == INARG_COUNT) ? srcType.returnType() : dstType.parameterType(i); |
| if (!VerifyType.isNullConversion(src, dst) || |
| level <= 1 && dst.isInterface() && !dst.isAssignableFrom(src)) { |
| needConv[i] = true; |
| conversions++; |
| } |
| } |
| boolean retConv = needConv[INARG_COUNT]; |
| |
| final int IN_MH = 0; |
| final int INARG_BASE = 1; |
| final int INARG_LIMIT = INARG_BASE + INARG_COUNT; |
| final int NAME_LIMIT = INARG_LIMIT + conversions + 1; |
| final int RETURN_CONV = (!retConv ? -1 : NAME_LIMIT - 1); |
| final int OUT_CALL = (!retConv ? NAME_LIMIT : RETURN_CONV) - 1; |
| |
| // Now build a LambdaForm. |
| MethodType lambdaType = srcType.basicType().invokerType(); |
| Name[] names = arguments(NAME_LIMIT - INARG_LIMIT, lambdaType); |
| |
| // Collect the arguments to the outgoing call, maybe with conversions: |
| final int OUTARG_BASE = 0; // target MH is Name.function, name Name.arguments[0] |
| Object[] outArgs = new Object[OUTARG_BASE + INARG_COUNT]; |
| |
| int nameCursor = INARG_LIMIT; |
| for (int i = 0; i < INARG_COUNT; i++) { |
| Class<?> src = srcType.parameterType(i); |
| Class<?> dst = dstType.parameterType(i); |
| |
| if (!needConv[i]) { |
| // do nothing: difference is trivial |
| outArgs[OUTARG_BASE + i] = names[INARG_BASE + i]; |
| continue; |
| } |
| |
| // Tricky case analysis follows. |
| MethodHandle fn = null; |
| if (src.isPrimitive()) { |
| if (dst.isPrimitive()) { |
| fn = ValueConversions.convertPrimitive(src, dst); |
| } else { |
| Wrapper w = Wrapper.forPrimitiveType(src); |
| MethodHandle boxMethod = ValueConversions.box(w); |
| if (dst == w.wrapperType()) |
| fn = boxMethod; |
| else |
| fn = boxMethod.asType(MethodType.methodType(dst, src)); |
| } |
| } else { |
| if (dst.isPrimitive()) { |
| // Caller has boxed a primitive. Unbox it for the target. |
| Wrapper w = Wrapper.forPrimitiveType(dst); |
| if (level == 0 || VerifyType.isNullConversion(src, w.wrapperType())) { |
| fn = ValueConversions.unbox(dst); |
| } else if (src == Object.class || !Wrapper.isWrapperType(src)) { |
| // Examples: Object->int, Number->int, Comparable->int; Byte->int, Character->int |
| // must include additional conversions |
| // src must be examined at runtime, to detect Byte, Character, etc. |
| MethodHandle unboxMethod = (level == 1 |
| ? ValueConversions.unbox(dst) |
| : ValueConversions.unboxCast(dst)); |
| fn = unboxMethod; |
| } else { |
| // Example: Byte->int |
| // Do this by reformulating the problem to Byte->byte. |
| Class<?> srcPrim = Wrapper.forWrapperType(src).primitiveType(); |
| MethodHandle unbox = ValueConversions.unbox(srcPrim); |
| // Compose the two conversions. FIXME: should make two Names for this job |
| fn = unbox.asType(MethodType.methodType(dst, src)); |
| } |
| } else { |
| // Simple reference conversion. |
| // Note: Do not check for a class hierarchy relation |
| // between src and dst. In all cases a 'null' argument |
| // will pass the cast conversion. |
| fn = ValueConversions.cast(dst); |
| } |
| } |
| Name conv = new Name(fn, names[INARG_BASE + i]); |
| assert(names[nameCursor] == null); |
| names[nameCursor++] = conv; |
| assert(outArgs[OUTARG_BASE + i] == null); |
| outArgs[OUTARG_BASE + i] = conv; |
| } |
| |
| // Build argument array for the call. |
| assert(nameCursor == OUT_CALL); |
| names[OUT_CALL] = new Name(target, outArgs); |
| |
| if (RETURN_CONV < 0) { |
| assert(OUT_CALL == names.length-1); |
| } else { |
| Class<?> needReturn = srcType.returnType(); |
| Class<?> haveReturn = dstType.returnType(); |
| MethodHandle fn; |
| Object[] arg = { names[OUT_CALL] }; |
| if (haveReturn == void.class) { |
| // synthesize a zero value for the given void |
| Object zero = Wrapper.forBasicType(needReturn).zero(); |
| fn = MethodHandles.constant(needReturn, zero); |
| arg = new Object[0]; // don't pass names[OUT_CALL] to conversion |
| } else { |
| MethodHandle identity = MethodHandles.identity(needReturn); |
| MethodType needConversion = identity.type().changeParameterType(0, haveReturn); |
| fn = makePairwiseConvert(identity, needConversion, level); |
| } |
| assert(names[RETURN_CONV] == null); |
| names[RETURN_CONV] = new Name(fn, arg); |
| assert(RETURN_CONV == names.length-1); |
| } |
| |
| LambdaForm form = new LambdaForm("convert", lambdaType.parameterCount(), names); |
| return SimpleMethodHandle.make(srcType, form); |
| } |
| |
| static MethodHandle makeReferenceIdentity(Class<?> refType) { |
| MethodType lambdaType = MethodType.genericMethodType(1).invokerType(); |
| Name[] names = arguments(1, lambdaType); |
| names[names.length - 1] = new Name(ValueConversions.identity(), names[1]); |
| LambdaForm form = new LambdaForm("identity", lambdaType.parameterCount(), names); |
| return SimpleMethodHandle.make(MethodType.methodType(refType, refType), form); |
| } |
| |
| static MethodHandle makeVarargsCollector(MethodHandle target, Class<?> arrayType) { |
| MethodType type = target.type(); |
| int last = type.parameterCount() - 1; |
| if (type.parameterType(last) != arrayType) |
| target = target.asType(type.changeParameterType(last, arrayType)); |
| target = target.asFixedArity(); // make sure this attribute is turned off |
| return new AsVarargsCollector(target, target.type(), arrayType); |
| } |
| |
| static class AsVarargsCollector extends MethodHandle { |
| private final MethodHandle target; |
| private final Class<?> arrayType; |
| private /*@Stable*/ MethodHandle asCollectorCache; |
| |
| AsVarargsCollector(MethodHandle target, MethodType type, Class<?> arrayType) { |
| super(type, reinvokerForm(target)); |
| this.target = target; |
| this.arrayType = arrayType; |
| this.asCollectorCache = target.asCollector(arrayType, 0); |
| } |
| |
| @Override MethodHandle reinvokerTarget() { return target; } |
| |
| @Override |
| public boolean isVarargsCollector() { |
| return true; |
| } |
| |
| @Override |
| public MethodHandle asFixedArity() { |
| return target; |
| } |
| |
| @Override |
| public MethodHandle asTypeUncached(MethodType newType) { |
| MethodType type = this.type(); |
| int collectArg = type.parameterCount() - 1; |
| int newArity = newType.parameterCount(); |
| if (newArity == collectArg+1 && |
| type.parameterType(collectArg).isAssignableFrom(newType.parameterType(collectArg))) { |
| // if arity and trailing parameter are compatible, do normal thing |
| return asTypeCache = asFixedArity().asType(newType); |
| } |
| // check cache |
| MethodHandle acc = asCollectorCache; |
| if (acc != null && acc.type().parameterCount() == newArity) |
| return asTypeCache = acc.asType(newType); |
| // build and cache a collector |
| int arrayLength = newArity - collectArg; |
| MethodHandle collector; |
| try { |
| collector = asFixedArity().asCollector(arrayType, arrayLength); |
| assert(collector.type().parameterCount() == newArity) : "newArity="+newArity+" but collector="+collector; |
| } catch (IllegalArgumentException ex) { |
| throw new WrongMethodTypeException("cannot build collector", ex); |
| } |
| asCollectorCache = collector; |
| return asTypeCache = collector.asType(newType); |
| } |
| |
| @Override |
| MethodHandle setVarargs(MemberName member) { |
| if (member.isVarargs()) return this; |
| return asFixedArity(); |
| } |
| |
| @Override |
| MethodHandle viewAsType(MethodType newType) { |
| if (newType.lastParameterType() != type().lastParameterType()) |
| throw new InternalError(); |
| MethodHandle newTarget = asFixedArity().viewAsType(newType); |
| // put back the varargs bit: |
| return new AsVarargsCollector(newTarget, newType, arrayType); |
| } |
| |
| @Override |
| MemberName internalMemberName() { |
| return asFixedArity().internalMemberName(); |
| } |
| @Override |
| Class<?> internalCallerClass() { |
| return asFixedArity().internalCallerClass(); |
| } |
| |
| /*non-public*/ |
| @Override |
| boolean isInvokeSpecial() { |
| return asFixedArity().isInvokeSpecial(); |
| } |
| |
| |
| @Override |
| MethodHandle bindArgument(int pos, char basicType, Object value) { |
| return asFixedArity().bindArgument(pos, basicType, value); |
| } |
| |
| @Override |
| MethodHandle bindReceiver(Object receiver) { |
| return asFixedArity().bindReceiver(receiver); |
| } |
| |
| @Override |
| MethodHandle dropArguments(MethodType srcType, int pos, int drops) { |
| return asFixedArity().dropArguments(srcType, pos, drops); |
| } |
| |
| @Override |
| MethodHandle permuteArguments(MethodType newType, int[] reorder) { |
| return asFixedArity().permuteArguments(newType, reorder); |
| } |
| } |
| |
| /** Factory method: Spread selected argument. */ |
| static MethodHandle makeSpreadArguments(MethodHandle target, |
| Class<?> spreadArgType, int spreadArgPos, int spreadArgCount) { |
| MethodType targetType = target.type(); |
| |
| for (int i = 0; i < spreadArgCount; i++) { |
| Class<?> arg = VerifyType.spreadArgElementType(spreadArgType, i); |
| if (arg == null) arg = Object.class; |
| targetType = targetType.changeParameterType(spreadArgPos + i, arg); |
| } |
| target = target.asType(targetType); |
| |
| MethodType srcType = targetType |
| .replaceParameterTypes(spreadArgPos, spreadArgPos + spreadArgCount, spreadArgType); |
| // Now build a LambdaForm. |
| MethodType lambdaType = srcType.invokerType(); |
| Name[] names = arguments(spreadArgCount + 2, lambdaType); |
| int nameCursor = lambdaType.parameterCount(); |
| int[] indexes = new int[targetType.parameterCount()]; |
| |
| for (int i = 0, argIndex = 1; i < targetType.parameterCount() + 1; i++, argIndex++) { |
| Class<?> src = lambdaType.parameterType(i); |
| if (i == spreadArgPos) { |
| // Spread the array. |
| MethodHandle aload = MethodHandles.arrayElementGetter(spreadArgType); |
| Name array = names[argIndex]; |
| names[nameCursor++] = new Name(Lazy.NF_checkSpreadArgument, array, spreadArgCount); |
| for (int j = 0; j < spreadArgCount; i++, j++) { |
| indexes[i] = nameCursor; |
| names[nameCursor++] = new Name(aload, array, j); |
| } |
| } else if (i < indexes.length) { |
| indexes[i] = argIndex; |
| } |
| } |
| assert(nameCursor == names.length-1); // leave room for the final call |
| |
| // Build argument array for the call. |
| Name[] targetArgs = new Name[targetType.parameterCount()]; |
| for (int i = 0; i < targetType.parameterCount(); i++) { |
| int idx = indexes[i]; |
| targetArgs[i] = names[idx]; |
| } |
| names[names.length - 1] = new Name(target, (Object[]) targetArgs); |
| |
| LambdaForm form = new LambdaForm("spread", lambdaType.parameterCount(), names); |
| return SimpleMethodHandle.make(srcType, form); |
| } |
| |
| static void checkSpreadArgument(Object av, int n) { |
| if (av == null) { |
| if (n == 0) return; |
| } else if (av instanceof Object[]) { |
| int len = ((Object[])av).length; |
| if (len == n) return; |
| } else { |
| int len = java.lang.reflect.Array.getLength(av); |
| if (len == n) return; |
| } |
| // fall through to error: |
| throw newIllegalArgumentException("array is not of length "+n); |
| } |
| |
| /** |
| * Pre-initialized NamedFunctions for bootstrapping purposes. |
| * Factored in an inner class to delay initialization until first usage. |
| */ |
| private static class Lazy { |
| private static final Class<?> MHI = MethodHandleImpl.class; |
| |
| static final NamedFunction NF_checkSpreadArgument; |
| static final NamedFunction NF_guardWithCatch; |
| static final NamedFunction NF_selectAlternative; |
| static final NamedFunction NF_throwException; |
| |
| static { |
| try { |
| NF_checkSpreadArgument = new NamedFunction(MHI.getDeclaredMethod("checkSpreadArgument", Object.class, int.class)); |
| NF_guardWithCatch = new NamedFunction(MHI.getDeclaredMethod("guardWithCatch", MethodHandle.class, Class.class, |
| MethodHandle.class, Object[].class)); |
| NF_selectAlternative = new NamedFunction(MHI.getDeclaredMethod("selectAlternative", boolean.class, MethodHandle.class, |
| MethodHandle.class)); |
| NF_throwException = new NamedFunction(MHI.getDeclaredMethod("throwException", Throwable.class)); |
| |
| NF_checkSpreadArgument.resolve(); |
| NF_guardWithCatch.resolve(); |
| NF_selectAlternative.resolve(); |
| NF_throwException.resolve(); |
| } catch (ReflectiveOperationException ex) { |
| throw newInternalError(ex); |
| } |
| } |
| } |
| |
| /** Factory method: Collect or filter selected argument(s). */ |
| static MethodHandle makeCollectArguments(MethodHandle target, |
| MethodHandle collector, int collectArgPos, boolean retainOriginalArgs) { |
| MethodType targetType = target.type(); // (a..., c, [b...])=>r |
| MethodType collectorType = collector.type(); // (b...)=>c |
| int collectArgCount = collectorType.parameterCount(); |
| Class<?> collectValType = collectorType.returnType(); |
| int collectValCount = (collectValType == void.class ? 0 : 1); |
| MethodType srcType = targetType // (a..., [b...])=>r |
| .dropParameterTypes(collectArgPos, collectArgPos+collectValCount); |
| if (!retainOriginalArgs) { // (a..., b...)=>r |
| srcType = srcType.insertParameterTypes(collectArgPos, collectorType.parameterList()); |
| } |
| // in arglist: [0: ...keep1 | cpos: collect... | cpos+cacount: keep2... ] |
| // out arglist: [0: ...keep1 | cpos: collectVal? | cpos+cvcount: keep2... ] |
| // out(retain): [0: ...keep1 | cpos: cV? coll... | cpos+cvc+cac: keep2... ] |
| |
| // Now build a LambdaForm. |
| MethodType lambdaType = srcType.invokerType(); |
| Name[] names = arguments(2, lambdaType); |
| final int collectNamePos = names.length - 2; |
| final int targetNamePos = names.length - 1; |
| |
| Name[] collectorArgs = Arrays.copyOfRange(names, 1 + collectArgPos, 1 + collectArgPos + collectArgCount); |
| names[collectNamePos] = new Name(collector, (Object[]) collectorArgs); |
| |
| // Build argument array for the target. |
| // Incoming LF args to copy are: [ (mh) headArgs collectArgs tailArgs ]. |
| // Output argument array is [ headArgs (collectVal)? (collectArgs)? tailArgs ]. |
| Name[] targetArgs = new Name[targetType.parameterCount()]; |
| int inputArgPos = 1; // incoming LF args to copy to target |
| int targetArgPos = 0; // fill pointer for targetArgs |
| int chunk = collectArgPos; // |headArgs| |
| System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk); |
| inputArgPos += chunk; |
| targetArgPos += chunk; |
| if (collectValType != void.class) { |
| targetArgs[targetArgPos++] = names[collectNamePos]; |
| } |
| chunk = collectArgCount; |
| if (retainOriginalArgs) { |
| System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk); |
| targetArgPos += chunk; // optionally pass on the collected chunk |
| } |
| inputArgPos += chunk; |
| chunk = targetArgs.length - targetArgPos; // all the rest |
| System.arraycopy(names, inputArgPos, targetArgs, targetArgPos, chunk); |
| assert(inputArgPos + chunk == collectNamePos); // use of rest of input args also |
| names[targetNamePos] = new Name(target, (Object[]) targetArgs); |
| |
| LambdaForm form = new LambdaForm("collect", lambdaType.parameterCount(), names); |
| return SimpleMethodHandle.make(srcType, form); |
| } |
| |
| @LambdaForm.Hidden |
| static |
| MethodHandle selectAlternative(boolean testResult, MethodHandle target, MethodHandle fallback) { |
| return testResult ? target : fallback; |
| } |
| |
| static |
| MethodHandle makeGuardWithTest(MethodHandle test, |
| MethodHandle target, |
| MethodHandle fallback) { |
| MethodType basicType = target.type().basicType(); |
| MethodHandle invokeBasic = MethodHandles.basicInvoker(basicType); |
| int arity = basicType.parameterCount(); |
| int extraNames = 3; |
| MethodType lambdaType = basicType.invokerType(); |
| Name[] names = arguments(extraNames, lambdaType); |
| |
| Object[] testArgs = Arrays.copyOfRange(names, 1, 1 + arity, Object[].class); |
| Object[] targetArgs = Arrays.copyOfRange(names, 0, 1 + arity, Object[].class); |
| |
| // call test |
| names[arity + 1] = new Name(test, testArgs); |
| |
| // call selectAlternative |
| Object[] selectArgs = { names[arity + 1], target, fallback }; |
| names[arity + 2] = new Name(Lazy.NF_selectAlternative, selectArgs); |
| targetArgs[0] = names[arity + 2]; |
| |
| // call target or fallback |
| names[arity + 3] = new Name(new NamedFunction(invokeBasic), targetArgs); |
| |
| LambdaForm form = new LambdaForm("guard", lambdaType.parameterCount(), names); |
| return SimpleMethodHandle.make(target.type(), form); |
| } |
| |
| /** |
| * The LambaForm shape for catchException combinator is the following: |
| * <blockquote><pre>{@code |
| * guardWithCatch=Lambda(a0:L,a1:L,a2:L)=>{ |
| * t3:L=BoundMethodHandle$Species_LLLLL.argL0(a0:L); |
| * t4:L=BoundMethodHandle$Species_LLLLL.argL1(a0:L); |
| * t5:L=BoundMethodHandle$Species_LLLLL.argL2(a0:L); |
| * t6:L=BoundMethodHandle$Species_LLLLL.argL3(a0:L); |
| * t7:L=BoundMethodHandle$Species_LLLLL.argL4(a0:L); |
| * t8:L=MethodHandle.invokeBasic(t6:L,a1:L,a2:L); |
| * t9:L=MethodHandleImpl.guardWithCatch(t3:L,t4:L,t5:L,t8:L); |
| * t10:I=MethodHandle.invokeBasic(t7:L,t9:L);t10:I} |
| * }</pre></blockquote> |
| * |
| * argL0 and argL2 are target and catcher method handles. argL1 is exception class. |
| * argL3 and argL4 are auxiliary method handles: argL3 boxes arguments and wraps them into Object[] |
| * (ValueConversions.array()) and argL4 unboxes result if necessary (ValueConversions.unbox()). |
| * |
| * Having t8 and t10 passed outside and not hardcoded into a lambda form allows to share lambda forms |
| * among catchException combinators with the same basic type. |
| */ |
| private static LambdaForm makeGuardWithCatchForm(MethodType basicType) { |
| MethodType lambdaType = basicType.invokerType(); |
| |
| LambdaForm lform = basicType.form().cachedLambdaForm(MethodTypeForm.LF_GWC); |
| if (lform != null) { |
| return lform; |
| } |
| final int THIS_MH = 0; // the BMH_LLLLL |
| final int ARG_BASE = 1; // start of incoming arguments |
| final int ARG_LIMIT = ARG_BASE + basicType.parameterCount(); |
| |
| int nameCursor = ARG_LIMIT; |
| final int GET_TARGET = nameCursor++; |
| final int GET_CLASS = nameCursor++; |
| final int GET_CATCHER = nameCursor++; |
| final int GET_COLLECT_ARGS = nameCursor++; |
| final int GET_UNBOX_RESULT = nameCursor++; |
| final int BOXED_ARGS = nameCursor++; |
| final int TRY_CATCH = nameCursor++; |
| final int UNBOX_RESULT = nameCursor++; |
| |
| Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType); |
| |
| BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL(); |
| names[GET_TARGET] = new Name(data.getterFunction(0), names[THIS_MH]); |
| names[GET_CLASS] = new Name(data.getterFunction(1), names[THIS_MH]); |
| names[GET_CATCHER] = new Name(data.getterFunction(2), names[THIS_MH]); |
| names[GET_COLLECT_ARGS] = new Name(data.getterFunction(3), names[THIS_MH]); |
| names[GET_UNBOX_RESULT] = new Name(data.getterFunction(4), names[THIS_MH]); |
| |
| // FIXME: rework argument boxing/result unboxing logic for LF interpretation |
| |
| // t_{i}:L=MethodHandle.invokeBasic(collectArgs:L,a1:L,...); |
| MethodType collectArgsType = basicType.changeReturnType(Object.class); |
| MethodHandle invokeBasic = MethodHandles.basicInvoker(collectArgsType); |
| Object[] args = new Object[invokeBasic.type().parameterCount()]; |
| args[0] = names[GET_COLLECT_ARGS]; |
| System.arraycopy(names, ARG_BASE, args, 1, ARG_LIMIT-ARG_BASE); |
| names[BOXED_ARGS] = new Name(new NamedFunction(invokeBasic), args); |
| |
| // t_{i+1}:L=MethodHandleImpl.guardWithCatch(target:L,exType:L,catcher:L,t_{i}:L); |
| Object[] gwcArgs = new Object[] {names[GET_TARGET], names[GET_CLASS], names[GET_CATCHER], names[BOXED_ARGS]}; |
| names[TRY_CATCH] = new Name(Lazy.NF_guardWithCatch, gwcArgs); |
| |
| // t_{i+2}:I=MethodHandle.invokeBasic(unbox:L,t_{i+1}:L); |
| MethodHandle invokeBasicUnbox = MethodHandles.basicInvoker(MethodType.methodType(basicType.rtype(), Object.class)); |
| Object[] unboxArgs = new Object[] {names[GET_UNBOX_RESULT], names[TRY_CATCH]}; |
| names[UNBOX_RESULT] = new Name(new NamedFunction(invokeBasicUnbox), unboxArgs); |
| |
| lform = new LambdaForm("guardWithCatch", lambdaType.parameterCount(), names); |
| |
| basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWC, lform); |
| return lform; |
| } |
| |
| static |
| MethodHandle makeGuardWithCatch(MethodHandle target, |
| Class<? extends Throwable> exType, |
| MethodHandle catcher) { |
| MethodType type = target.type(); |
| LambdaForm form = makeGuardWithCatchForm(type.basicType()); |
| |
| // Prepare auxiliary method handles used during LambdaForm interpreation. |
| // Box arguments and wrap them into Object[]: ValueConversions.array(). |
| MethodType varargsType = type.changeReturnType(Object[].class); |
| MethodHandle collectArgs = ValueConversions.varargsArray(type.parameterCount()) |
| .asType(varargsType); |
| // Result unboxing: ValueConversions.unbox() OR ValueConversions.identity() OR ValueConversions.ignore(). |
| MethodHandle unboxResult; |
| if (type.returnType().isPrimitive()) { |
| unboxResult = ValueConversions.unbox(type.returnType()); |
| } else { |
| unboxResult = ValueConversions.identity(); |
| } |
| |
| BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLLLL(); |
| BoundMethodHandle mh; |
| try { |
| mh = (BoundMethodHandle) |
| data.constructor[0].invokeBasic(type, form, (Object) target, (Object) exType, (Object) catcher, |
| (Object) collectArgs, (Object) unboxResult); |
| } catch (Throwable ex) { |
| throw uncaughtException(ex); |
| } |
| assert(mh.type() == type); |
| return mh; |
| } |
| |
| /** |
| * Intrinsified during LambdaForm compilation |
| * (see {@link InvokerBytecodeGenerator#emitGuardWithCatch emitGuardWithCatch}). |
| */ |
| @LambdaForm.Hidden |
| static Object guardWithCatch(MethodHandle target, Class<? extends Throwable> exType, MethodHandle catcher, |
| Object... av) throws Throwable { |
| try { |
| return target.invokeWithArguments(av); |
| } catch (Throwable t) { |
| if (!exType.isInstance(t)) throw t; |
| Object[] args = prepend(t, av); |
| return catcher.invokeWithArguments(args); |
| } |
| } |
| |
| /** Prepend an element {@code elem} to an {@code array}. */ |
| private static Object[] prepend(Object elem, Object[] array) { |
| Object[] newArray = new Object[array.length+1]; |
| newArray[0] = elem; |
| System.arraycopy(array, 0, newArray, 1, array.length); |
| return newArray; |
| } |
| |
| static |
| MethodHandle throwException(MethodType type) { |
| assert(Throwable.class.isAssignableFrom(type.parameterType(0))); |
| int arity = type.parameterCount(); |
| if (arity > 1) { |
| return throwException(type.dropParameterTypes(1, arity)).dropArguments(type, 1, arity-1); |
| } |
| return makePairwiseConvert(Lazy.NF_throwException.resolvedHandle(), type, 2); |
| } |
| |
| static <T extends Throwable> Empty throwException(T t) throws T { throw t; } |
| |
| static MethodHandle[] FAKE_METHOD_HANDLE_INVOKE = new MethodHandle[2]; |
| static MethodHandle fakeMethodHandleInvoke(MemberName method) { |
| int idx; |
| assert(method.isMethodHandleInvoke()); |
| switch (method.getName()) { |
| case "invoke": idx = 0; break; |
| case "invokeExact": idx = 1; break; |
| default: throw new InternalError(method.getName()); |
| } |
| MethodHandle mh = FAKE_METHOD_HANDLE_INVOKE[idx]; |
| if (mh != null) return mh; |
| MethodType type = MethodType.methodType(Object.class, UnsupportedOperationException.class, |
| MethodHandle.class, Object[].class); |
| mh = throwException(type); |
| mh = mh.bindTo(new UnsupportedOperationException("cannot reflectively invoke MethodHandle")); |
| if (!method.getInvocationType().equals(mh.type())) |
| throw new InternalError(method.toString()); |
| mh = mh.withInternalMemberName(method); |
| mh = mh.asVarargsCollector(Object[].class); |
| assert(method.isVarargs()); |
| FAKE_METHOD_HANDLE_INVOKE[idx] = mh; |
| return mh; |
| } |
| |
| /** |
| * Create an alias for the method handle which, when called, |
| * appears to be called from the same class loader and protection domain |
| * as hostClass. |
| * This is an expensive no-op unless the method which is called |
| * is sensitive to its caller. A small number of system methods |
| * are in this category, including Class.forName and Method.invoke. |
| */ |
| static |
| MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) { |
| return BindCaller.bindCaller(mh, hostClass); |
| } |
| |
| // Put the whole mess into its own nested class. |
| // That way we can lazily load the code and set up the constants. |
| private static class BindCaller { |
| static |
| MethodHandle bindCaller(MethodHandle mh, Class<?> hostClass) { |
| // Do not use this function to inject calls into system classes. |
| if (hostClass == null |
| || (hostClass.isArray() || |
| hostClass.isPrimitive() || |
| hostClass.getName().startsWith("java.") || |
| hostClass.getName().startsWith("sun."))) { |
| throw new InternalError(); // does not happen, and should not anyway |
| } |
| // For simplicity, convert mh to a varargs-like method. |
| MethodHandle vamh = prepareForInvoker(mh); |
| // Cache the result of makeInjectedInvoker once per argument class. |
| MethodHandle bccInvoker = CV_makeInjectedInvoker.get(hostClass); |
| return restoreToType(bccInvoker.bindTo(vamh), mh.type(), mh.internalMemberName(), hostClass); |
| } |
| |
| private static MethodHandle makeInjectedInvoker(Class<?> hostClass) { |
| Class<?> bcc = UNSAFE.defineAnonymousClass(hostClass, T_BYTES, null); |
| if (hostClass.getClassLoader() != bcc.getClassLoader()) |
| throw new InternalError(hostClass.getName()+" (CL)"); |
| try { |
| if (hostClass.getProtectionDomain() != bcc.getProtectionDomain()) |
| throw new InternalError(hostClass.getName()+" (PD)"); |
| } catch (SecurityException ex) { |
| // Self-check was blocked by security manager. This is OK. |
| // In fact the whole try body could be turned into an assertion. |
| } |
| try { |
| MethodHandle init = IMPL_LOOKUP.findStatic(bcc, "init", MethodType.methodType(void.class)); |
| init.invokeExact(); // force initialization of the class |
| } catch (Throwable ex) { |
| throw uncaughtException(ex); |
| } |
| MethodHandle bccInvoker; |
| try { |
| MethodType invokerMT = MethodType.methodType(Object.class, MethodHandle.class, Object[].class); |
| bccInvoker = IMPL_LOOKUP.findStatic(bcc, "invoke_V", invokerMT); |
| } catch (ReflectiveOperationException ex) { |
| throw uncaughtException(ex); |
| } |
| // Test the invoker, to ensure that it really injects into the right place. |
| try { |
| MethodHandle vamh = prepareForInvoker(MH_checkCallerClass); |
| Object ok = bccInvoker.invokeExact(vamh, new Object[]{hostClass, bcc}); |
| } catch (Throwable ex) { |
| throw new InternalError(ex); |
| } |
| return bccInvoker; |
| } |
| private static ClassValue<MethodHandle> CV_makeInjectedInvoker = new ClassValue<MethodHandle>() { |
| @Override protected MethodHandle computeValue(Class<?> hostClass) { |
| return makeInjectedInvoker(hostClass); |
| } |
| }; |
| |
| // Adapt mh so that it can be called directly from an injected invoker: |
| private static MethodHandle prepareForInvoker(MethodHandle mh) { |
| mh = mh.asFixedArity(); |
| MethodType mt = mh.type(); |
| int arity = mt.parameterCount(); |
| MethodHandle vamh = mh.asType(mt.generic()); |
| vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames |
| vamh = vamh.asSpreader(Object[].class, arity); |
| vamh.internalForm().compileToBytecode(); // eliminate LFI stack frames |
| return vamh; |
| } |
| |
| // Undo the adapter effect of prepareForInvoker: |
| private static MethodHandle restoreToType(MethodHandle vamh, MethodType type, |
| MemberName member, |
| Class<?> hostClass) { |
| MethodHandle mh = vamh.asCollector(Object[].class, type.parameterCount()); |
| mh = mh.asType(type); |
| mh = new WrappedMember(mh, type, member, hostClass); |
| return mh; |
| } |
| |
| private static final MethodHandle MH_checkCallerClass; |
| static { |
| final Class<?> THIS_CLASS = BindCaller.class; |
| assert(checkCallerClass(THIS_CLASS, THIS_CLASS)); |
| try { |
| MH_checkCallerClass = IMPL_LOOKUP |
| .findStatic(THIS_CLASS, "checkCallerClass", |
| MethodType.methodType(boolean.class, Class.class, Class.class)); |
| assert((boolean) MH_checkCallerClass.invokeExact(THIS_CLASS, THIS_CLASS)); |
| } catch (Throwable ex) { |
| throw new InternalError(ex); |
| } |
| } |
| |
| @CallerSensitive |
| private static boolean checkCallerClass(Class<?> expected, Class<?> expected2) { |
| // This method is called via MH_checkCallerClass and so it's |
| // correct to ask for the immediate caller here. |
| Class<?> actual = Reflection.getCallerClass(); |
| if (actual != expected && actual != expected2) |
| throw new InternalError("found "+actual.getName()+", expected "+expected.getName() |
| +(expected == expected2 ? "" : ", or else "+expected2.getName())); |
| return true; |
| } |
| |
| private static final byte[] T_BYTES; |
| static { |
| final Object[] values = {null}; |
| AccessController.doPrivileged(new PrivilegedAction<Void>() { |
| public Void run() { |
| try { |
| Class<T> tClass = T.class; |
| String tName = tClass.getName(); |
| String tResource = tName.substring(tName.lastIndexOf('.')+1)+".class"; |
| java.net.URLConnection uconn = tClass.getResource(tResource).openConnection(); |
| int len = uconn.getContentLength(); |
| byte[] bytes = new byte[len]; |
| try (java.io.InputStream str = uconn.getInputStream()) { |
| int nr = str.read(bytes); |
| if (nr != len) throw new java.io.IOException(tResource); |
| } |
| values[0] = bytes; |
| } catch (java.io.IOException ex) { |
| throw new InternalError(ex); |
| } |
| return null; |
| } |
| }); |
| T_BYTES = (byte[]) values[0]; |
| } |
| |
| // The following class is used as a template for Unsafe.defineAnonymousClass: |
| private static class T { |
| static void init() { } // side effect: initializes this class |
| static Object invoke_V(MethodHandle vamh, Object[] args) throws Throwable { |
| return vamh.invokeExact(args); |
| } |
| } |
| } |
| |
| |
| /** This subclass allows a wrapped method handle to be re-associated with an arbitrary member name. */ |
| static class WrappedMember extends MethodHandle { |
| private final MethodHandle target; |
| private final MemberName member; |
| private final Class<?> callerClass; |
| |
| private WrappedMember(MethodHandle target, MethodType type, MemberName member, Class<?> callerClass) { |
| super(type, reinvokerForm(target)); |
| this.target = target; |
| this.member = member; |
| this.callerClass = callerClass; |
| } |
| |
| @Override |
| MethodHandle reinvokerTarget() { |
| return target; |
| } |
| @Override |
| public MethodHandle asTypeUncached(MethodType newType) { |
| // This MH is an alias for target, except for the MemberName |
| // Drop the MemberName if there is any conversion. |
| return asTypeCache = target.asType(newType); |
| } |
| @Override |
| MemberName internalMemberName() { |
| return member; |
| } |
| @Override |
| Class<?> internalCallerClass() { |
| return callerClass; |
| } |
| @Override |
| boolean isInvokeSpecial() { |
| return target.isInvokeSpecial(); |
| } |
| @Override |
| MethodHandle viewAsType(MethodType newType) { |
| return new WrappedMember(target, newType, member, callerClass); |
| } |
| } |
| |
| static MethodHandle makeWrappedMember(MethodHandle target, MemberName member) { |
| if (member.equals(target.internalMemberName())) |
| return target; |
| return new WrappedMember(target, target.type(), member, null); |
| } |
| |
| } |
