# HG changeset patch
# User srastogi
# Date 1460555294 -7200
# Node ID f6abe5d4bb1d1e78b8093b43eba3e96e17b8457b
# Parent 931e55c1287da022f3d33090cc434fa53a02411d
8150829: Enhanced drop-args, identity and default constant, varargs adjustment
Reviewed-by: psandoz, mhaupt, jrose
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/src/java.base/share/classes/java/lang/invoke/MethodHandle.java
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandle.java Wed Apr 13 14:29:25 2016 +0100
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandle.java Wed Apr 13 15:48:14 2016 +0200
@@ -219,7 +219,8 @@
* Method handles produced by lookups or constant loads from methods or
* constructors with the variable arity modifier bit ({@code 0x0080})
* have a corresponding variable arity, as if they were defined with
- * the help of {@link #asVarargsCollector asVarargsCollector}.
+ * the help of {@link #asVarargsCollector asVarargsCollector}
+ * or {@link #withVarargs withVarargs}.
* <p>
* A method reference may refer either to a static or non-static method.
* In the non-static case, the method handle type includes an explicit
@@ -972,6 +973,36 @@
throw newIllegalArgumentException("array length is not legal for long[] or double[]", arrayLength);
}
}
+ /**
+ * Adapts this method handle to be {@linkplain #asVarargsCollector variable arity}
+ * if the boolean flag is true, else {@linkplain #asFixedArity fixed arity}.
+ * If the method handle is already of the proper arity mode, it is returned
+ * unchanged.
+ * @apiNote
+ * <p>This method is sometimes useful when adapting a method handle that
+ * may be variable arity, to ensure that the resulting adapter is also
+ * variable arity if and only if the original handle was. For example,
+ * this code changes the first argument of a handle {@code mh} to {@code int} without
+ * disturbing its variable arity property:
+ * {@code mh.asType(mh.type().changeParameterType(0,int.class))
+ * .withVarargs(mh.isVarargsCollector())}
+ * @param makeVarargs true if the return method handle should have variable arity behavior
+ * @return a method handle of the same type, with possibly adjusted variable arity behavior
+ * @throws IllegalArgumentException if {@code makeVarargs} is true and
+ * this method handle does not have a trailing array parameter
+ * @since 9
+ * @see #asVarargsCollector
+ * @see #asFixedArity
+ */
+ public MethodHandle withVarargs(boolean makeVarargs) {
+ if (!makeVarargs) {
+ return asFixedArity();
+ } else if (!isVarargsCollector()) {
+ return asVarargsCollector(type().lastParameterType());
+ } else {
+ return this;
+ }
+ }
/**
* Makes an <em>array-collecting</em> method handle, which accepts a given number of trailing
@@ -1000,7 +1031,8 @@
* to allow the target to use a simple {@code Object} as its last parameter type.)
* <p>
* In order to create a collecting adapter which is not restricted to a particular
- * number of collected arguments, use {@link #asVarargsCollector asVarargsCollector} instead.
+ * number of collected arguments, use {@link #asVarargsCollector asVarargsCollector}
+ * or {@link #withVarargs withVarargs} instead.
* <p>
* Here are some examples of array-collecting method handles:
* <blockquote><pre>{@code
@@ -1216,7 +1248,7 @@
* <p>
* No method handle transformations produce new method handles with
* variable arity, unless they are documented as doing so.
- * Therefore, besides {@code asVarargsCollector},
+ * Therefore, besides {@code asVarargsCollector} and {@code withVarargs},
* all methods in {@code MethodHandle} and {@code MethodHandles}
* will return a method handle with fixed arity,
* except in the cases where they are specified to return their original
@@ -1273,6 +1305,7 @@
* or {@code arrayType} is not assignable to this method handle's trailing parameter type
* @see #asCollector
* @see #isVarargsCollector
+ * @see #withVarargs
* @see #asFixedArity
*/
public MethodHandle asVarargsCollector(Class<?> arrayType) {
@@ -1344,6 +1377,7 @@
* @return a new method handle which accepts only a fixed number of arguments
* @see #asVarargsCollector
* @see #isVarargsCollector
+ * @see #withVarargs
*/
public MethodHandle asFixedArity() {
assert(!isVarargsCollector());
@@ -1428,11 +1462,11 @@
/*non-public*/
MethodHandle setVarargs(MemberName member) throws IllegalAccessException {
if (!member.isVarargs()) return this;
- Class<?> arrayType = type().lastParameterType();
- if (arrayType.isArray()) {
- return MethodHandleImpl.makeVarargsCollector(this, arrayType);
+ try {
+ return this.withVarargs(true);
+ } catch (IllegalArgumentException ex) {
+ throw member.makeAccessException("cannot make variable arity", null);
}
- throw member.makeAccessException("cannot make variable arity", null);
}
/*non-public*/
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java Wed Apr 13 14:29:25 2016 +0100
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java Wed Apr 13 15:48:14 2016 +0200
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2008, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2016, 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
@@ -1055,7 +1055,7 @@
if (!method.getInvocationType().equals(mh.type()))
throw new InternalError(method.toString());
mh = mh.withInternalMemberName(method, false);
- mh = mh.asVarargsCollector(Object[].class);
+ mh = mh.withVarargs(true);
assert(method.isVarargs());
FAKE_METHOD_HANDLE_INVOKE[idx] = mh;
return mh;
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleProxies.java
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleProxies.java Wed Apr 13 14:29:25 2016 +0100
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleProxies.java Wed Apr 13 15:48:14 2016 +0200
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2016, 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
@@ -216,13 +216,7 @@
}
private static MethodHandle bindCaller(MethodHandle target, Class<?> hostClass) {
- MethodHandle cbmh = MethodHandleImpl.bindCaller(target, hostClass);
- if (target.isVarargsCollector()) {
- MethodType type = cbmh.type();
- int arity = type.parameterCount();
- return cbmh.asVarargsCollector(type.parameterType(arity-1));
- }
- return cbmh;
+ return MethodHandleImpl.bindCaller(target, hostClass).withVarargs(target.isVarargsCollector());
}
/**
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Wed Apr 13 14:29:25 2016 +0100
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Wed Apr 13 15:48:14 2016 +0200
@@ -1352,9 +1352,7 @@
...
MethodHandle mh0 = lookup().findVirtual(defc, name, type);
MethodHandle mh1 = mh0.bindTo(receiver);
-MethodType mt1 = mh1.type();
-if (mh0.isVarargsCollector())
- mh1 = mh1.asVarargsCollector(mt1.parameterType(mt1.parameterCount()-1));
+mh1 = mh1.withVarargs(mh0.isVarargsCollector());
return mh1;
* }</pre></blockquote>
* where {@code defc} is either {@code receiver.getClass()} or a super
@@ -2951,9 +2949,55 @@
if (ident.type().returnType() == type)
return ident;
// something like identity(Foo.class); do not bother to intern these
- assert(btw == Wrapper.OBJECT);
+ assert (btw == Wrapper.OBJECT);
return makeIdentity(type);
}
+
+ /**
+ * Produces a constant method handle of the requested return type which
+ * returns the default value for that type every time it is invoked.
+ * The resulting constant method handle will have no side effects.
+ * <p>The returned method handle is equivalent to {@code empty(methodType(type))}.
+ * It is also equivalent to {@code explicitCastArguments(constant(Object.class, null), methodType(type))},
+ * since {@code explicitCastArguments} converts {@code null} to default values.
+ * @param type the expected return type of the desired method handle
+ * @return a constant method handle that takes no arguments
+ * and returns the default value of the given type (or void, if the type is void)
+ * @throws NullPointerException if the argument is null
+ * @see MethodHandles#constant
+ * @see MethodHandles#empty
+ * @since 9
+ */
+ public static MethodHandle zero(Class<?> type) {
+ Objects.requireNonNull(type);
+ return type.isPrimitive() ? zero(Wrapper.forPrimitiveType(type), type) : zero(Wrapper.OBJECT, type);
+ }
+
+ private static MethodHandle identityOrVoid(Class<?> type) {
+ return type == void.class ? zero(type) : identity(type);
+ }
+
+ /**
+ * Produces a method handle of the requested type which ignores any arguments, does nothing,
+ * and returns a suitable default depending on the return type.
+ * That is, it returns a zero primitive value, a {@code null}, or {@code void}.
+ * <p>The returned method handle is equivalent to
+ * {@code dropArguments(zero(type.returnType()), 0, type.parameterList())}.
+ * <p>
+ * @apiNote Given a predicate and target, a useful "if-then" construct can be produced as
+ * {@code guardWithTest(pred, target, empty(target.type())}.
+ * @param type the type of the desired method handle
+ * @return a constant method handle of the given type, which returns a default value of the given return type
+ * @throws NullPointerException if the argument is null
+ * @see MethodHandles#zero
+ * @see MethodHandles#constant
+ * @since 9
+ */
+ public static MethodHandle empty(MethodType type) {
+ Objects.requireNonNull(type);
+ return dropArguments(zero(type.returnType()), 0, type.parameterList());
+ }
+
private static final MethodHandle[] IDENTITY_MHS = new MethodHandle[Wrapper.values().length];
private static MethodHandle makeIdentity(Class<?> ptype) {
MethodType mtype = MethodType.methodType(ptype, ptype);
@@ -3145,8 +3189,7 @@
* If {@code pos} is zero, the dummy arguments will precede
* the target's real arguments; if {@code pos} is <i>N</i>
* they will come after.
- * <p>
- * <b>Example:</b>
+ * @apiNote
* <blockquote><pre>{@code
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;
@@ -3185,6 +3228,99 @@
return dropArguments(target, pos, Arrays.asList(valueTypes));
}
+ // private version which allows caller some freedom with error handling
+ private static MethodHandle dropArgumentsToMatch(MethodHandle target, int skip, List<Class<?>> newTypes, int pos,
+ boolean nullOnFailure) {
+ List<Class<?>> oldTypes = target.type().parameterList();
+ int match = oldTypes.size();
+ if (skip != 0) {
+ if (skip < 0 || skip > match) {
+ throw newIllegalArgumentException("illegal skip", skip, target);
+ }
+ oldTypes = oldTypes.subList(skip, match);
+ match -= skip;
+ }
+ List<Class<?>> addTypes = newTypes;
+ int add = addTypes.size();
+ if (pos != 0) {
+ if (pos < 0 || pos > add) {
+ throw newIllegalArgumentException("illegal pos", pos, newTypes);
+ }
+ addTypes = addTypes.subList(pos, add);
+ add -= pos; assert(addTypes.size() == add);
+ }
+ // Do not add types which already match the existing arguments.
+ if (match > add || !oldTypes.equals(addTypes.subList(0, match))) {
+ if (nullOnFailure) {
+ return null;
+ }
+ throw newIllegalArgumentException("argument lists do not match", oldTypes, newTypes);
+ }
+ addTypes = addTypes.subList(match, add);
+ add -= match; assert(addTypes.size() == add);
+ // newTypes: ( P*[pos], M*[match], A*[add] )
+ // target: ( S*[skip], M*[match] )
+ MethodHandle adapter = target;
+ if (add > 0) {
+ adapter = dropArguments(adapter, skip+ match, addTypes);
+ }
+ // adapter: (S*[skip], M*[match], A*[add] )
+ if (pos > 0) {
+ adapter = dropArguments(adapter, skip, newTypes.subList(0, pos));
+ }
+ // adapter: (S*[skip], P*[pos], M*[match], A*[add] )
+ return adapter;
+ }
+
+ /**
+ * Adapts a target method handle to match the given parameter type list, if necessary, by adding dummy arguments.
+ * Some leading parameters are first skipped; they will be left unchanged and are otherwise ignored.
+ * The remaining types in the target's parameter type list must be contained as a sub-list of the given type list,
+ * at the given position.
+ * Any non-matching parameter types (before or after the matching sub-list) are inserted in corresponding
+ * positions of the target method handle's parameters, as if by {@link #dropArguments}.
+ * (More precisely, elements in the new list before {@code pos} are inserted into the target list at {@code skip},
+ * while elements in the new list after the match beginning at {@code pos} are inserted at the end of the
+ * target list.)
+ * The target's return type will be unchanged.
+ * @apiNote
+ * Two method handles whose argument lists are "effectively identical" (i.e., identical
+ * in a common prefix) may be mutually converted to a common type
+ * by two calls to {@code dropArgumentsToMatch}, as follows:
+ * <blockquote><pre>{@code
+import static java.lang.invoke.MethodHandles.*;
+import static java.lang.invoke.MethodType.*;
+...
+...
+MethodHandle h0 = constant(boolean.class, true);
+MethodHandle h1 = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class));
+MethodType bigType = h1.type().insertParameterTypes(1, String.class, int.class);
+MethodHandle h2 = dropArguments(h1, 0, bigType.parameterList());
+if (h1.type().parameterCount() < h2.type().parameterCount())
+ h1 = dropArgumentsToMatch(h1, 0, h2.type().parameterList(), 0); // lengthen h1
+else
+ h2 = dropArgumentsToMatch(h2, 0, h1.type().parameterList(), 0); // lengthen h2
+MethodHandle h3 = guardWithTest(h0, h1, h2);
+assertEquals("xy", h3.invoke("x", "y", 1, "a", "b", "c"));
+ * }</pre></blockquote>
+ * @param target the method handle to adapt
+ * @param skip number of targets parameters to disregard (they will be unchanged)
+ * @param newTypes the desired argument list of the method handle
+ * @param pos place in {@code newTypes} where the non-skipped target parameters must occur
+ * @return a possibly adapted method handle
+ * @throws NullPointerException if either argument is null
+ * @throws IllegalArgumentException
+ * if either index is out of range in its corresponding list, or
+ * if the non-skipped target parameter types match the new types at {@code pos}
+ * @since 9
+ */
+ public static
+ MethodHandle dropArgumentsToMatch(MethodHandle target, int skip, List<Class<?>> newTypes, int pos) {
+ Objects.requireNonNull(target);
+ Objects.requireNonNull(newTypes);
+ return dropArgumentsToMatch(target, skip, newTypes, pos, false);
+ }
+
/**
* Adapts a target method handle by pre-processing
* one or more of its arguments, each with its own unary filter function,
@@ -3696,13 +3832,9 @@
if (gtype.returnType() != boolean.class)
throw newIllegalArgumentException("guard type is not a predicate "+gtype);
List<Class<?>> targs = ttype.parameterList();
- List<Class<?>> gargs = gtype.parameterList();
- if (!targs.equals(gargs)) {
- int gpc = gargs.size(), tpc = targs.size();
- if (gpc >= tpc || !targs.subList(0, gpc).equals(gargs))
- throw misMatchedTypes("target and test types", ttype, gtype);
- test = dropArguments(test, gpc, targs.subList(gpc, tpc));
- gtype = test.type();
+ test = dropArgumentsToMatch(test, 0, targs, 0, true);
+ if (test == null) {
+ throw misMatchedTypes("target and test types", ttype, gtype);
}
return MethodHandleImpl.makeGuardWithTest(test, target, fallback);
}
@@ -3774,15 +3906,9 @@
throw newIllegalArgumentException("handler does not accept exception type "+exType);
if (htype.returnType() != ttype.returnType())
throw misMatchedTypes("target and handler return types", ttype, htype);
- List<Class<?>> targs = ttype.parameterList();
- List<Class<?>> hargs = htype.parameterList();
- hargs = hargs.subList(1, hargs.size()); // omit leading parameter from handler
- if (!targs.equals(hargs)) {
- int hpc = hargs.size(), tpc = targs.size();
- if (hpc >= tpc || !targs.subList(0, hpc).equals(hargs))
- throw misMatchedTypes("target and handler types", ttype, htype);
- handler = dropArguments(handler, 1+hpc, targs.subList(hpc, tpc));
- htype = handler.type();
+ handler = dropArgumentsToMatch(handler, 1, ttype.parameterList(), 0, true);
+ if (handler == null) {
+ throw misMatchedTypes("target and handler types", ttype, htype);
}
return MethodHandleImpl.makeGuardWithCatch(target, exType, handler);
}
@@ -4040,16 +4166,16 @@
for (int i = 0; i < nclauses; ++i) {
Class<?> t = iterationVariableTypes.get(i);
if (init.get(i) == null) {
- init.set(i, zeroHandle(t));
+ init.set(i, empty(MethodType.methodType(t, commonSuffix)));
}
if (step.get(i) == null) {
- step.set(i, dropArguments(t == void.class ? zeroHandle(t) : identity(t), 0, commonPrefix.subList(0, i)));
+ step.set(i, dropArgumentsToMatch(identityOrVoid(t), 0, commonParameterSequence, i));
}
if (pred.get(i) == null) {
- pred.set(i, constant(boolean.class, true));
+ pred.set(i, dropArguments(constant(boolean.class, true), 0, commonParameterSequence));
}
if (fini.get(i) == null) {
- fini.set(i, zeroHandle(t));
+ fini.set(i, empty(MethodType.methodType(t, commonParameterSequence)));
}
}
@@ -4143,7 +4269,7 @@
* @since 9
*/
public static MethodHandle whileLoop(MethodHandle init, MethodHandle pred, MethodHandle body) {
- MethodHandle fin = init == null ? zeroHandle(void.class) : identity(init.type().returnType());
+ MethodHandle fin = init == null ? zero(void.class) : identity(init.type().returnType());
MethodHandle[] checkExit = {null, null, pred, fin};
MethodHandle[] varBody = {init, body};
return loop(checkExit, varBody);
@@ -4209,7 +4335,7 @@
* @since 9
*/
public static MethodHandle doWhileLoop(MethodHandle init, MethodHandle body, MethodHandle pred) {
- MethodHandle fin = init == null ? zeroHandle(void.class) : identity(init.type().returnType());
+ MethodHandle fin = init == null ? zero(void.class) : identity(init.type().returnType());
MethodHandle[] clause = {init, body, pred, fin};
return loop(clause);
}
@@ -4346,7 +4472,7 @@
* @since 9
*/
public static MethodHandle countedLoop(MethodHandle start, MethodHandle end, MethodHandle init, MethodHandle body) {
- MethodHandle returnVar = dropArguments(init == null ? zeroHandle(void.class) : identity(init.type().returnType()),
+ MethodHandle returnVar = dropArguments(init == null ? zero(void.class) : identity(init.type().returnType()),
0, int.class, int.class);
MethodHandle[] indexVar = {start, MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_countedLoopStep)};
MethodHandle[] loopLimit = {end, null, MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_countedLoopPred), returnVar};
@@ -4449,7 +4575,7 @@
Class<?> ttype = body.type().parameterType(0);
MethodHandle returnVar =
- dropArguments(init == null ? zeroHandle(void.class) : identity(init.type().returnType()), 0, itype);
+ dropArguments(init == null ? zero(void.class) : identity(init.type().returnType()), 0, itype);
MethodHandle initnx = MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_iterateNext);
MethodHandle nextVal = initnx.asType(initnx.type().changeReturnType(ttype));
@@ -4543,15 +4669,11 @@
checkTryFinally(target, cleanup);
// Match parameter lists: if the cleanup has a shorter parameter list than the target, add ignored arguments.
- int tpSize = targetParamTypes.size();
- int cpPrefixLength = rtype == void.class ? 1 : 2;
- int cpSize = cleanupParamTypes.size();
- MethodHandle aCleanup = cpSize - cpPrefixLength < tpSize ?
- dropArguments(cleanup, cpSize, targetParamTypes.subList(tpSize - (cpSize - cpPrefixLength), tpSize)) :
- cleanup;
-
+ // The cleanup parameter list (minus the leading Throwable and result parameters) must be a sublist of the
+ // target parameter list.
+ cleanup = dropArgumentsToMatch(cleanup, (rtype == void.class ? 1 : 2), targetParamTypes, 0);
MethodHandle aTarget = target.asSpreader(Object[].class, target.type().parameterCount());
- aCleanup = aCleanup.asSpreader(Object[].class, tpSize);
+ MethodHandle aCleanup = cleanup.asSpreader(Object[].class, targetParamTypes.size());
return MethodHandleImpl.makeTryFinally(aTarget, aCleanup, rtype, targetParamTypes);
}
@@ -4642,16 +4764,6 @@
return result;
}
- /**
- * Wrap creation of a proper zero handle for a given type.
- *
- * @param type the type.
- *
- * @return a zero value for the given type.
- */
- static MethodHandle zeroHandle(Class<?> type) {
- return type.isPrimitive() ? zero(Wrapper.forPrimitiveType(type), type) : zero(Wrapper.OBJECT, type);
- }
private static void checkLoop0(MethodHandle[][] clauses) {
if (clauses == null || clauses.length == 0) {
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/test/java/lang/invoke/ConstantIdentityMHTest.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/invoke/ConstantIdentityMHTest.java Wed Apr 13 15:48:14 2016 +0200
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+
+/* @test
+ * @summary unit tests for java.lang.invoke.MethodHandles
+ * @run testng/othervm -ea -esa test.java.lang.invoke.ConstantIdentityMHTest
+ */
+package test.java.lang.invoke;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.util.List;
+import static java.lang.invoke.MethodHandles.*;
+import static java.lang.invoke.MethodType.*;
+import static org.testng.AssertJUnit.*;
+import org.testng.annotations.*;
+
+public class ConstantIdentityMHTest {
+
+ @DataProvider(name = "testZeroData")
+ private Object[][] testZeroData() {
+ return new Object[][] {
+ {void.class, "()void"},
+ {int.class, "()int"},
+ {byte.class, "()byte"},
+ {short.class, "()short"},
+ {long.class, "()long"},
+ {float.class, "()float"},
+ {double.class, "()double"},
+ {boolean.class, "()boolean"},
+ {char.class, "()char"},
+ {Integer.class, "()Integer"}
+ };
+ }
+
+ @Test(dataProvider = "testZeroData")
+ public void testZero(Class<?> expectedtype, String expected) throws Throwable {
+ assertEquals(MethodHandles.zero(expectedtype).type().toString(), expected);
+ }
+
+ @Test
+ @ExpectedExceptions(NullPointerException.class)
+ public void testZeroNPE() {
+ MethodHandle mh = MethodHandles.zero(null);
+ }
+
+ @Test
+ void testEmpty() throws Throwable {
+ MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class));
+ assertEquals("xy", (String)cat.invoke("x","y"));
+ MethodHandle mhEmpty = MethodHandles.empty(cat.type());
+ assertEquals(null, (String)mhEmpty.invoke("x","y"));
+ }
+
+ @Test
+ @ExpectedExceptions(NullPointerException.class)
+ void testEmptyNPE() {
+ MethodHandle lenEmptyMH = MethodHandles.empty(null);
+ }
+}
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/test/java/lang/invoke/DropArgumentsTest.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/invoke/DropArgumentsTest.java Wed Apr 13 15:48:14 2016 +0200
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+
+/* @test
+ * @summary unit tests for java.lang.invoke.MethodHandles
+ * @run testng/othervm -ea -esa test.java.lang.invoke.DropArgumentsTest
+ */
+package test.java.lang.invoke;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.util.List;
+import static java.lang.invoke.MethodHandles.*;
+import static java.lang.invoke.MethodType.*;
+import static org.testng.AssertJUnit.*;
+import org.testng.annotations.*;
+
+public class DropArgumentsTest {
+
+ @Test
+ public void testDropArgumentsToMatch() throws Throwable {
+ MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class));
+ MethodType bigType = cat.type().insertParameterTypes(0, String.class, String.class, int.class);
+ MethodHandle d0 = MethodHandles.dropArgumentsToMatch(cat, 0, bigType.parameterList(), 3);
+ assertEquals("xy",(String)d0.invokeExact("m", "n", 1, "x", "y"));
+ MethodHandle d1 = MethodHandles.dropArgumentsToMatch(cat, 0, bigType.parameterList(), 0);
+ assertEquals("mn",(String)d1.invokeExact("m", "n", 1, "x", "y"));
+ MethodHandle d2 = MethodHandles.dropArgumentsToMatch(cat, 1, bigType.parameterList(), 4);
+ assertEquals("xy",(String)d2.invokeExact("x", "b", "c", 1, "a", "y"));
+
+ }
+
+ @DataProvider(name = "dropArgumentsToMatchNPEData")
+ private Object[][] dropArgumentsToMatchNPEData()
+ throws NoSuchMethodException, IllegalAccessException {
+ MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class));
+ return new Object[][] {
+ { (MethodHandle) null, 0, cat.type().parameterList(), 0 },
+ { cat, 0, null, 0 }
+ };
+ }
+
+ @Test(dataProvider = "dropArgumentsToMatchNPEData")
+ @ExpectedExceptions(NullPointerException.class)
+ public void dropArgumentsToMatchNPE(MethodHandle target, int pos, List<Class<?>> valueType, int skip) {
+ MethodHandles.dropArgumentsToMatch(target, pos, valueType , skip);
+ }
+
+ @DataProvider(name = "dropArgumentsToMatchIAEData")
+ private Object[][] dropArgumentsToMatchIAEData()
+ throws NoSuchMethodException, IllegalAccessException {
+ MethodHandle cat = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class));
+ MethodType bigType = cat.type().insertParameterTypes(0, String.class, String.class, int.class);
+ return new Object[][] {
+ {cat, -1, bigType.parameterList(), 0},
+ {cat, 0, bigType.parameterList(), -1},
+ {cat, 3, bigType.parameterList(), 0},
+ {cat, 0, bigType.parameterList(), 2}
+ };
+ }
+
+ @Test(dataProvider = "dropArgumentsToMatchIAEData")
+ @ExpectedExceptions(IllegalArgumentException.class)
+ public void dropArgumentsToMatchIAE(MethodHandle target, int pos, List<Class<?>> valueType, int skip) {
+ MethodHandles.dropArgumentsToMatch(target, pos, valueType , skip);
+ }
+}
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/test/java/lang/invoke/JavaDocExamplesTest.java
--- a/jdk/test/java/lang/invoke/JavaDocExamplesTest.java Wed Apr 13 14:29:25 2016 +0100
+++ b/jdk/test/java/lang/invoke/JavaDocExamplesTest.java Wed Apr 13 15:48:14 2016 +0200
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2009, 2016, 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
@@ -57,7 +57,9 @@
testFindVirtual();
testFindSpecial();
testPermuteArguments();
+ testZero();
testDropArguments();
+ testDropArgumentsToMatch();
testFilterArguments();
testFoldArguments();
testFoldArguments2();
@@ -235,6 +237,17 @@
}}
}
+@Test public void testZero() throws Throwable {
+ {{
+{} /// JAVADOC
+Class<?> type = Double.class;
+MethodHandle mh1 = MethodHandles.explicitCastArguments(MethodHandles.constant(Object.class, null), methodType(type));
+assertEquals("()Double", mh1.type().toString());
+MethodHandle mh2 = MethodHandles.empty(methodType(type));
+assertEquals("()Double", mh2.type().toString());
+ }}
+ }
+
@Test public void testDropArguments() throws Throwable {
{{
{} /// JAVADOC
@@ -262,6 +275,24 @@
}}
}
+ @Test public void testDropArgumentsToMatch() throws Throwable {
+ {{
+{} /// JAVADOC
+MethodHandle h0= constant(boolean.class, true);
+MethodHandle h1 = lookup().findVirtual(String.class, "concat", methodType(String.class, String.class));
+MethodType bigType = h1.type().insertParameterTypes(1, String.class, int.class);
+MethodHandle h2 = dropArguments(h1, 0, bigType.parameterList());
+if (h1.type().parameterCount() < h2.type().parameterCount()) {
+ h1 = dropArgumentsToMatch(h1, 0, h2.type().parameterList(), 0); // lengthen h1
+}
+else {
+ h2 = dropArgumentsToMatch(h2, 0, h1.type().parameterList(), 0); // lengthen h2
+}
+MethodHandle h3 = guardWithTest(h0, h1, h2);
+assertEquals("xy", h3.invoke("x", "y", 1, "a", "b", "c"));
+ }}
+ }
+
@Test public void testFilterArguments() throws Throwable {
{{
{} /// JAVADOC
diff -r 931e55c1287d -r f6abe5d4bb1d jdk/test/java/lang/invoke/VarArgsTest.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/invoke/VarArgsTest.java Wed Apr 13 15:48:14 2016 +0200
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2016, 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.
+ */
+
+/* @test
+ * @summary unit tests for java.lang.invoke.MethodHandles
+ * @run testng/othervm -ea -esa test.java.lang.invoke.VarArgsTest
+ */
+package test.java.lang.invoke;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.util.Arrays;
+import java.util.List;
+import static java.lang.invoke.MethodHandles.*;
+import static java.lang.invoke.MethodType.*;
+import static org.testng.AssertJUnit.*;
+import org.testng.annotations.*;
+
+public class VarArgsTest {
+
+ @Test
+ public void testWithVarargs() throws Throwable {
+ MethodHandle deepToString = publicLookup()
+ .findStatic(Arrays.class, "deepToString", methodType(String.class, Object[].class));
+ assertFalse(deepToString.isVarargsCollector());
+ MethodHandle ts = deepToString.withVarargs(false);
+ assertFalse(ts.isVarargsCollector());
+ MethodHandle ts1 = deepToString.withVarargs(true);
+ assertTrue(ts1.isVarargsCollector());
+ assertEquals("[won]", (String) ts1.invokeExact(new Object[]{"won"}));
+ assertEquals("[won]", (String) ts1.invoke(new Object[]{"won"}));
+ assertEquals("[won]", (String) ts1.invoke("won"));
+ assertEquals("[won, won]", (String) ts1.invoke("won", "won"));
+ assertEquals("[won, won]", (String) ts1.invoke(new Object[]{"won", "won"}));
+ assertEquals("[[won]]", (String) ts1.invoke((Object) new Object[]{"won"}));
+ }
+
+ @Test
+ public void testWithVarargs2() throws Throwable {
+ MethodHandle asList = publicLookup()
+ .findStatic(Arrays.class, "asList", methodType(List.class, Object[].class));
+ MethodHandle asListWithVarargs = asList.withVarargs(asList.isVarargsCollector());
+ assert(asListWithVarargs.isVarargsCollector());
+ assertEquals("[]", asListWithVarargs.invoke().toString());
+ assertEquals("[1]", asListWithVarargs.invoke(1).toString());
+ assertEquals("[two, too]", asListWithVarargs.invoke("two", "too").toString());
+ }
+
+ @Test
+ @ExpectedExceptions(IllegalArgumentException.class)
+ public void testWithVarargsIAE() throws Throwable {
+ MethodHandle lenMH = publicLookup()
+ .findVirtual(String.class, "length", methodType(int.class));
+ MethodHandle lenMHWithVarargs = lenMH.withVarargs(true);
+ }
+
+}