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/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandleInfo;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodHandles.Lookup;
import java.lang.invoke.MethodType;
import java.lang.invoke.WrongMethodTypeException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.function.Consumer;
import other.Chatty;
public class Main {
public static class A {
public A() {}
public void foo() {
System.out.println("foo_A");
}
public static final Lookup lookup = MethodHandles.lookup();
}
public static class B extends A {
public void foo() {
System.out.println("foo_B");
}
public static final Lookup lookup = MethodHandles.lookup();
}
public static class C extends B {
public static final Lookup lookup = MethodHandles.lookup();
}
public static class D {
private final void privateRyan() {
System.out.println("privateRyan_D");
}
public static final Lookup lookup = MethodHandles.lookup();
}
public static class E extends D {
public static final Lookup lookup = MethodHandles.lookup();
}
private interface F {
public default void sayHi() {
System.out.println("F.sayHi()");
}
}
public static class G implements F {
public void sayHi() {
System.out.println("G.sayHi()");
}
public MethodHandles.Lookup getLookup() {
return MethodHandles.lookup();
}
}
public static class H implements Chatty {
public void chatter() {
System.out.println("H.chatter()");
}
public MethodHandles.Lookup getLookup() {
return MethodHandles.lookup();
}
}
public static void main(String[] args) throws Throwable {
testfindSpecial_invokeSuperBehaviour();
testfindSpecial_invokeDirectBehaviour();
testExceptionDetailMessages();
testfindVirtual();
testfindStatic();
testUnreflects();
testAsType();
testConstructors();
testStringConstructors();
testReturnValues();
testReturnValueConversions();
testVariableArity();
testVariableArity_MethodHandles_bind();
testRevealDirect();
testReflectiveCalls();
testInterfaceSpecial();
}
public static void testfindSpecial_invokeSuperBehaviour() throws Throwable {
// This is equivalent to an invoke-super instruction where the referrer
// is B.class.
MethodHandle mh1 = B.lookup.findSpecial(A.class /* refC */, "foo",
MethodType.methodType(void.class), B.class /* specialCaller */);
A aInstance = new A();
B bInstance = new B();
C cInstance = new C();
// This should be as if an invoke-super was called from one of B's methods.
mh1.invokeExact(bInstance);
mh1.invoke(bInstance);
// This should not work. The receiver type in the handle will be suitably
// restricted to B and subclasses.
try {
mh1.invoke(aInstance);
System.out.println("mh1.invoke(aInstance) should not succeeed");
} catch (ClassCastException expected) {
}
try {
mh1.invokeExact(aInstance);
System.out.println("mh1.invoke(aInstance) should not succeeed");
} catch (WrongMethodTypeException expected) {
}
// This should *still* be as if an invoke-super was called from one of C's
// methods, despite the fact that we're operating on a C.
mh1.invoke(cInstance);
// Now that C is the special caller, the next invoke will call B.foo.
MethodHandle mh2 = C.lookup.findSpecial(A.class /* refC */, "foo",
MethodType.methodType(void.class), C.class /* specialCaller */);
mh2.invokeExact(cInstance);
// Shouldn't allow invoke-super semantics from an unrelated special caller.
try {
C.lookup.findSpecial(A.class, "foo",
MethodType.methodType(void.class), D.class /* specialCaller */);
System.out.println("findSpecial(A.class, foo, .. D.class) unexpectedly succeeded.");
} catch (IllegalAccessException expected) {
}
// Check return type matches for find.
try {
B.lookup.findSpecial(A.class /* refC */, "foo",
MethodType.methodType(int.class), B.class /* specialCaller */);
fail();
} catch (NoSuchMethodException e) {}
// Check constructors
try {
B.lookup.findSpecial(A.class /* refC */, "<init>",
MethodType.methodType(void.class), B.class /* specialCaller */);
fail();
} catch (NoSuchMethodException e) {}
}
public static void testfindSpecial_invokeDirectBehaviour() throws Throwable {
D dInstance = new D();
MethodHandle mh3 = D.lookup.findSpecial(D.class, "privateRyan",
MethodType.methodType(void.class), D.class /* specialCaller */);
mh3.invoke(dInstance);
// The private method shouldn't be accessible from any special caller except
// itself...
try {
D.lookup.findSpecial(D.class, "privateRyan", MethodType.methodType(void.class), C.class);
System.out.println("findSpecial(privateRyan, C.class) unexpectedly succeeded");
} catch (IllegalAccessException expected) {
}
// ... or from any lookup context except its own.
try {
E.lookup.findSpecial(D.class, "privateRyan", MethodType.methodType(void.class), E.class);
System.out.println("findSpecial(privateRyan, E.class) unexpectedly succeeded");
} catch (IllegalAccessException expected) {
}
}
public static void testExceptionDetailMessages() throws Throwable {
MethodHandle handle = MethodHandles.lookup().findVirtual(String.class, "concat",
MethodType.methodType(String.class, String.class));
try {
handle.invokeExact("a", new Object());
System.out.println("invokeExact(\"a\", new Object()) unexpectedly succeeded.");
} catch (WrongMethodTypeException ex) {
System.out.println("Received WrongMethodTypeException exception");
}
}
public interface Foo {
public String foo();
}
public interface Bar extends Foo {
public String bar();
}
public static abstract class BarAbstractSuper {
public abstract String abstractSuperPublicMethod();
}
public static class BarSuper extends BarAbstractSuper {
public String superPublicMethod() {
return "superPublicMethod";
}
protected String superProtectedMethod() {
return "superProtectedMethod";
}
public String abstractSuperPublicMethod() {
return "abstractSuperPublicMethod";
}
String superPackageMethod() {
return "superPackageMethod";
}
}
public static class BarImpl extends BarSuper implements Bar {
public BarImpl() {
}
@Override
public String foo() {
return "foo";
}
@Override
public String bar() {
return "bar";
}
public String add(int x, int y) {
return Arrays.toString(new int[] { x, y });
}
private String privateMethod() { return "privateMethod"; }
public static String staticMethod() { return staticString; }
private static String staticString;
{
// Static constructor
staticString = Long.toString(System.currentTimeMillis());
}
static final MethodHandles.Lookup lookup = MethodHandles.lookup();
}
public static void testfindVirtual() throws Throwable {
// Virtual lookups on static methods should not succeed.
try {
MethodHandles.lookup().findVirtual(
BarImpl.class, "staticMethod", MethodType.methodType(String.class));
System.out.println("findVirtual(staticMethod) unexpectedly succeeded");
} catch (IllegalAccessException expected) {
}
// Virtual lookups on private methods should not succeed, unless the Lookup
// context had sufficient privileges.
try {
MethodHandles.lookup().findVirtual(
BarImpl.class, "privateMethod", MethodType.methodType(String.class));
System.out.println("findVirtual(privateMethod) unexpectedly succeeded");
} catch (IllegalAccessException expected) {
}
// Virtual lookup on a private method with a context that *does* have sufficient
// privileges.
MethodHandle mh = BarImpl.lookup.findVirtual(
BarImpl.class, "privateMethod", MethodType.methodType(String.class));
String str = (String) mh.invoke(new BarImpl());
if (!"privateMethod".equals(str)) {
System.out.println("Unexpected return value for BarImpl#privateMethod: " + str);
}
// Find virtual must find interface methods defined by interfaces implemented
// by the class.
mh = MethodHandles.lookup().findVirtual(BarImpl.class, "foo",
MethodType.methodType(String.class));
str = (String) mh.invoke(new BarImpl());
if (!"foo".equals(str)) {
System.out.println("Unexpected return value for BarImpl#foo: " + str);
}
// Find virtual should check rtype.
try {
mh = MethodHandles.lookup().findVirtual(BarImpl.class, "foo",
MethodType.methodType(void.class));
fail();
} catch (NoSuchMethodException e) {}
// And ptypes
mh = MethodHandles.lookup().findVirtual(
BarImpl.class, "add", MethodType.methodType(String.class, int.class, int.class));
try {
mh = MethodHandles.lookup().findVirtual(
BarImpl.class, "add", MethodType.methodType(String.class, Integer.class, int.class));
} catch (NoSuchMethodException e) {}
// .. and their super-interfaces.
mh = MethodHandles.lookup().findVirtual(BarImpl.class, "bar",
MethodType.methodType(String.class));
str = (String) mh.invoke(new BarImpl());
if (!"bar".equals(str)) {
System.out.println("Unexpected return value for BarImpl#bar: " + str);
}
mh = MethodHandles.lookup().findVirtual(Bar.class, "bar",
MethodType.methodType(String.class));
str = (String) mh.invoke(new BarImpl());
if (!"bar".equals(str)) {
System.out.println("Unexpected return value for BarImpl#bar: " + str);
}
mh = MethodHandles.lookup().findVirtual(BarAbstractSuper.class, "abstractSuperPublicMethod",
MethodType.methodType(String.class));
str = (String) mh.invoke(new BarImpl());
if (!"abstractSuperPublicMethod".equals(str)) {
System.out.println("Unexpected return value for BarImpl#abstractSuperPublicMethod: " + str);
}
// We should also be able to lookup public / protected / package methods in
// the super class, given sufficient access privileges.
mh = MethodHandles.lookup().findVirtual(BarImpl.class, "superPublicMethod",
MethodType.methodType(String.class));
str = (String) mh.invoke(new BarImpl());
if (!"superPublicMethod".equals(str)) {
System.out.println("Unexpected return value for BarImpl#superPublicMethod: " + str);
}
mh = MethodHandles.lookup().findVirtual(BarImpl.class, "superProtectedMethod",
MethodType.methodType(String.class));
str = (String) mh.invoke(new BarImpl());
if (!"superProtectedMethod".equals(str)) {
System.out.println("Unexpected return value for BarImpl#superProtectedMethod: " + str);
}
mh = MethodHandles.lookup().findVirtual(BarImpl.class, "superPackageMethod",
MethodType.methodType(String.class));
str = (String) mh.invoke(new BarImpl());
if (!"superPackageMethod".equals(str)) {
System.out.println("Unexpected return value for BarImpl#superPackageMethod: " + str);
}
try {
MethodHandles.lookup().findVirtual(BarImpl.class, "<init>",
MethodType.methodType(void.class));
fail();
} catch (NoSuchMethodException e) {}
}
public static void testfindStatic() throws Throwable {
MethodHandles.lookup().findStatic(BarImpl.class, "staticMethod",
MethodType.methodType(String.class));
try {
MethodHandles.lookup().findStatic(BarImpl.class, "staticMethod",
MethodType.methodType(void.class));
fail();
} catch (NoSuchMethodException e) {}
try {
MethodHandles.lookup().findStatic(BarImpl.class, "staticMethod",
MethodType.methodType(String.class, int.class));
fail();
} catch (NoSuchMethodException e) {}
try {
MethodHandles.lookup().findStatic(BarImpl.class, "<clinit>",
MethodType.methodType(void.class));
fail();
} catch (NoSuchMethodException e) {}
try {
MethodHandles.lookup().findStatic(BarImpl.class, "<init>",
MethodType.methodType(void.class));
fail();
} catch (NoSuchMethodException e) {}
}
static class UnreflectTester {
public String publicField;
private String privateField;
public static String publicStaticField = "publicStaticValue";
private static String privateStaticField = "privateStaticValue";
private UnreflectTester(String val) {
publicField = val;
privateField = val;
}
// NOTE: The boolean constructor argument only exists to give this a
// different signature.
public UnreflectTester(String val, boolean unused) {
this(val);
}
private static String privateStaticMethod() {
return "privateStaticMethod";
}
private String privateMethod() {
return "privateMethod";
}
public static String publicStaticMethod() {
return "publicStaticMethod";
}
public String publicMethod() {
return "publicMethod";
}
public String publicVarArgsMethod(String... args) {
return "publicVarArgsMethod";
}
}
public static void testUnreflects() throws Throwable {
UnreflectTester instance = new UnreflectTester("unused");
Method publicMethod = UnreflectTester.class.getMethod("publicMethod");
MethodHandle mh = MethodHandles.lookup().unreflect(publicMethod);
assertEquals("publicMethod", (String) mh.invoke(instance));
assertEquals("publicMethod", (String) mh.invokeExact(instance));
Method publicStaticMethod = UnreflectTester.class.getMethod("publicStaticMethod");
mh = MethodHandles.lookup().unreflect(publicStaticMethod);
assertEquals("publicStaticMethod", (String) mh.invoke());
assertEquals("publicStaticMethod", (String) mh.invokeExact());
Method privateMethod = UnreflectTester.class.getDeclaredMethod("privateMethod");
try {
mh = MethodHandles.lookup().unreflect(privateMethod);
fail();
} catch (IllegalAccessException expected) {}
privateMethod.setAccessible(true);
mh = MethodHandles.lookup().unreflect(privateMethod);
assertEquals("privateMethod", (String) mh.invoke(instance));
assertEquals("privateMethod", (String) mh.invokeExact(instance));
Method privateStaticMethod = UnreflectTester.class.getDeclaredMethod("privateStaticMethod");
try {
mh = MethodHandles.lookup().unreflect(privateStaticMethod);
fail();
} catch (IllegalAccessException expected) {}
privateStaticMethod.setAccessible(true);
mh = MethodHandles.lookup().unreflect(privateStaticMethod);
assertEquals("privateStaticMethod", (String) mh.invoke());
assertEquals("privateStaticMethod", (String) mh.invokeExact());
Constructor privateConstructor = UnreflectTester.class.getDeclaredConstructor(String.class);
try {
mh = MethodHandles.lookup().unreflectConstructor(privateConstructor);
fail();
} catch (IllegalAccessException expected) {}
privateConstructor.setAccessible(true);
mh = MethodHandles.lookup().unreflectConstructor(privateConstructor);
instance = (UnreflectTester) mh.invokeExact("abc");
assertEquals("abc", instance.publicField);
instance = (UnreflectTester) mh.invoke("def");
assertEquals("def", instance.publicField);
Constructor publicConstructor = UnreflectTester.class.getConstructor(String.class,
boolean.class);
mh = MethodHandles.lookup().unreflectConstructor(publicConstructor);
instance = (UnreflectTester) mh.invokeExact("abc", false);
assertEquals("abc", instance.publicField);
instance = (UnreflectTester) mh.invoke("def", true);
assertEquals("def", instance.publicField);
// TODO(narayan): Non exact invokes for field sets/gets are not implemented yet.
//
// assertEquals("instanceValue", (String) mh.invoke(new UnreflectTester("instanceValue")));
Field publicField = UnreflectTester.class.getField("publicField");
mh = MethodHandles.lookup().unreflectGetter(publicField);
instance = new UnreflectTester("instanceValue");
assertEquals("instanceValue", (String) mh.invokeExact(instance));
mh = MethodHandles.lookup().unreflectSetter(publicField);
instance = new UnreflectTester("instanceValue");
mh.invokeExact(instance, "updatedInstanceValue");
assertEquals("updatedInstanceValue", instance.publicField);
Field publicStaticField = UnreflectTester.class.getField("publicStaticField");
mh = MethodHandles.lookup().unreflectGetter(publicStaticField);
UnreflectTester.publicStaticField = "updatedStaticValue";
assertEquals("updatedStaticValue", (String) mh.invokeExact());
mh = MethodHandles.lookup().unreflectSetter(publicStaticField);
UnreflectTester.publicStaticField = "updatedStaticValue";
mh.invokeExact("updatedStaticValue2");
assertEquals("updatedStaticValue2", UnreflectTester.publicStaticField);
Field privateField = UnreflectTester.class.getDeclaredField("privateField");
try {
mh = MethodHandles.lookup().unreflectGetter(privateField);
fail();
} catch (IllegalAccessException expected) {
}
try {
mh = MethodHandles.lookup().unreflectSetter(privateField);
fail();
} catch (IllegalAccessException expected) {
}
privateField.setAccessible(true);
mh = MethodHandles.lookup().unreflectGetter(privateField);
instance = new UnreflectTester("instanceValue");
assertEquals("instanceValue", (String) mh.invokeExact(instance));
mh = MethodHandles.lookup().unreflectSetter(privateField);
instance = new UnreflectTester("instanceValue");
mh.invokeExact(instance, "updatedInstanceValue");
assertEquals("updatedInstanceValue", instance.privateField);
Field privateStaticField = UnreflectTester.class.getDeclaredField("privateStaticField");
try {
mh = MethodHandles.lookup().unreflectGetter(privateStaticField);
fail();
} catch (IllegalAccessException expected) {
}
try {
mh = MethodHandles.lookup().unreflectSetter(privateStaticField);
fail();
} catch (IllegalAccessException expected) {
}
privateStaticField.setAccessible(true);
mh = MethodHandles.lookup().unreflectGetter(privateStaticField);
privateStaticField.set(null, "updatedStaticValue");
assertEquals("updatedStaticValue", (String) mh.invokeExact());
mh = MethodHandles.lookup().unreflectSetter(privateStaticField);
privateStaticField.set(null, "updatedStaticValue");
mh.invokeExact("updatedStaticValue2");
assertEquals("updatedStaticValue2", (String) privateStaticField.get(null));
// unreflectSpecial testing - F is an interface that G implements
G g = new G();
g.sayHi(); // prints "G.sayHi()"
MethodHandles.Lookup lookupInG = g.getLookup();
Method methodInG = G.class.getDeclaredMethod("sayHi");
lookupInG.unreflectSpecial(methodInG, G.class).invoke(g); // prints "G.sayHi()"
Method methodInF = F.class.getDeclaredMethod("sayHi");
lookupInG.unreflect(methodInF).invoke(g); // prints "G.sayHi()"
lookupInG.in(G.class).unreflectSpecial(methodInF, G.class).invoke(g); // prints "F.sayHi()"
lookupInG.unreflectSpecial(methodInF, G.class).bindTo(g).invokeWithArguments();
// unreflectSpecial testing - other.Chatty is an interface that H implements
H h = new H();
h.chatter();
MethodHandles.Lookup lookupInH = h.getLookup();
Method methodInH = H.class.getDeclaredMethod("chatter");
lookupInH.unreflectSpecial(methodInH, H.class).invoke(h);
Method methodInChatty = Chatty.class.getDeclaredMethod("chatter");
lookupInH.unreflect(methodInChatty).invoke(h);
lookupInH.in(H.class).unreflectSpecial(methodInChatty, H.class).invoke(h);
lookupInH.unreflectSpecial(methodInChatty, H.class).bindTo(h).invokeWithArguments();
}
// This method only exists to fool Jack's handling of types. See b/32536744.
public static CharSequence getSequence() {
return "foo";
}
public static void testAsType() throws Throwable {
// The type of this handle is (String, String)String.
MethodHandle mh = MethodHandles.lookup().findVirtual(String.class,
"concat", MethodType.methodType(String.class, String.class));
// Change it to (CharSequence, String)Object.
MethodHandle asType = mh.asType(
MethodType.methodType(Object.class, CharSequence.class, String.class));
Object obj = asType.invokeExact((CharSequence) getSequence(), "bar");
assertEquals("foobar", (String) obj);
// Should fail due to a wrong return type.
try {
String str = (String) asType.invokeExact((CharSequence) getSequence(), "bar");
fail();
} catch (WrongMethodTypeException expected) {
}
// Should fail due to a wrong argument type (String instead of Charsequence).
try {
String str = (String) asType.invokeExact("baz", "bar");
fail();
} catch (WrongMethodTypeException expected) {
}
// Calls to asType should fail if the types are not convertible.
//
// Bad return type conversion.
try {
mh.asType(MethodType.methodType(int.class, String.class, String.class));
fail();
} catch (WrongMethodTypeException expected) {
}
// Bad argument conversion.
try {
mh.asType(MethodType.methodType(String.class, int.class, String.class));
fail();
} catch (WrongMethodTypeException expected) {
}
}
public static void assertTrue(boolean value) {
if (!value) {
throw new AssertionError("assertTrue value: " + value);
}
}
public static void assertFalse(boolean value) {
if (value) {
throw new AssertionError("assertTrue value: " + value);
}
}
public static void assertEquals(int i1, int i2) {
if (i1 == i2) { return; }
throw new AssertionError("assertEquals i1: " + i1 + ", i2: " + i2);
}
public static void assertEquals(long i1, long i2) {
if (i1 == i2) { return; }
throw new AssertionError("assertEquals l1: " + i1 + ", l2: " + i2);
}
public static void assertEquals(Object o, Object p) {
if (o == p) { return; }
if (o != null && p != null && o.equals(p)) { return; }
throw new AssertionError("assertEquals: o1: " + o + ", o2: " + p);
}
public static void assertEquals(String s1, String s2) {
if (s1 == s2) {
return;
}
if (s1 != null && s2 != null && s1.equals(s2)) {
return;
}
throw new AssertionError("assertEquals s1: " + s1 + ", s2: " + s2);
}
public static void fail() {
System.out.println("fail");
Thread.dumpStack();
}
public static void fail(String message) {
System.out.println("fail: " + message);
Thread.dumpStack();
}
public static void testConstructors() throws Throwable {
MethodHandle mh =
MethodHandles.lookup().findConstructor(Float.class,
MethodType.methodType(void.class,
float.class));
Float value = (Float) mh.invokeExact(0.33f);
if (value.floatValue() != 0.33f) {
fail("Unexpected float value from invokeExact " + value.floatValue());
}
value = (Float) mh.invoke(3.34f);
if (value.floatValue() != 3.34f) {
fail("Unexpected float value from invoke " + value.floatValue());
}
mh = MethodHandles.lookup().findConstructor(Double.class,
MethodType.methodType(void.class, String.class));
Double d = (Double) mh.invoke("8.45e3");
if (d.doubleValue() != 8.45e3) {
fail("Unexpected double value from Double(String) " + value.doubleValue());
}
mh = MethodHandles.lookup().findConstructor(Double.class,
MethodType.methodType(void.class, double.class));
d = (Double) mh.invoke(8.45e3);
if (d.doubleValue() != 8.45e3) {
fail("Unexpected double value from Double(double) " + value.doubleValue());
}
// Primitive type
try {
mh = MethodHandles.lookup().findConstructor(int.class, MethodType.methodType(void.class));
fail("Unexpected lookup success for primitive constructor");
} catch (NoSuchMethodException e) {}
// Interface
try {
mh = MethodHandles.lookup().findConstructor(Readable.class,
MethodType.methodType(void.class));
fail("Unexpected lookup success for interface constructor");
} catch (NoSuchMethodException e) {}
// Abstract
mh = MethodHandles.lookup().findConstructor(Process.class, MethodType.methodType(void.class));
try {
mh.invoke();
fail("Unexpected ability to instantiate an abstract class");
} catch (InstantiationException e) {}
// Non-existent
try {
MethodHandle bad = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(String.class, Float.class));
fail("Unexpected success for non-existent constructor");
} catch (NoSuchMethodException e) {}
// Non-void constructor search. (I)I instead of (I)V.
try {
MethodHandle foo = MethodHandles.lookup().findConstructor(
Integer.class, MethodType.methodType(Integer.class, Integer.class));
fail("Unexpected success for non-void type for findConstructor");
} catch (NoSuchMethodException e) {}
// Array class constructor.
try {
MethodHandle foo = MethodHandles.lookup().findConstructor(
Object[].class, MethodType.methodType(void.class));
fail("Unexpected success for array class type for findConstructor");
} catch (NoSuchMethodException e) {}
}
public static void testStringConstructors() throws Throwable {
final String testPattern = "The system as we know it is broken";
// String()
MethodHandle mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class));
String s = (String) mh.invokeExact();
if (!s.equals("")) {
fail("Unexpected empty string constructor result: '" + s + "'");
}
// String(String)
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, String.class));
s = (String) mh.invokeExact(testPattern);
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(char[])
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, char[].class));
s = (String) mh.invokeExact(testPattern.toCharArray());
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(char[], int, int)
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, char[].class, int.class, int.class));
s = (String) mh.invokeExact(new char [] { 'a', 'b', 'c', 'd', 'e'}, 2, 3);
if (!s.equals("cde")) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(int[] codePoints, int offset, int count)
StringBuffer sb = new StringBuffer(testPattern);
int[] codePoints = new int[sb.codePointCount(0, sb.length())];
for (int i = 0; i < sb.length(); ++i) {
codePoints[i] = sb.codePointAt(i);
}
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, int[].class, int.class, int.class));
s = (String) mh.invokeExact(codePoints, 0, codePoints.length);
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(byte ascii[], int hibyte, int offset, int count)
byte [] ascii = testPattern.getBytes(StandardCharsets.US_ASCII);
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, byte[].class, int.class, int.class));
s = (String) mh.invokeExact(ascii, 0, ascii.length);
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(byte bytes[], int offset, int length, String charsetName)
mh = MethodHandles.lookup().findConstructor(
String.class,
MethodType.methodType(void.class, byte[].class, int.class, int.class, String.class));
s = (String) mh.invokeExact(ascii, 0, 5, StandardCharsets.US_ASCII.name());
if (!s.equals(testPattern.substring(0, 5))) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(byte bytes[], int offset, int length, Charset charset)
mh = MethodHandles.lookup().findConstructor(
String.class,
MethodType.methodType(void.class, byte[].class, int.class, int.class, Charset.class));
s = (String) mh.invokeExact(ascii, 0, 5, StandardCharsets.US_ASCII);
if (!s.equals(testPattern.substring(0, 5))) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(byte bytes[], String charsetName)
mh = MethodHandles.lookup().findConstructor(
String.class,
MethodType.methodType(void.class, byte[].class, String.class));
s = (String) mh.invokeExact(ascii, StandardCharsets.US_ASCII.name());
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(byte bytes[], Charset charset)
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, byte[].class, Charset.class));
s = (String) mh.invokeExact(ascii, StandardCharsets.US_ASCII);
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(byte bytes[], int offset, int length)
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, byte[].class, int.class, int.class));
s = (String) mh.invokeExact(ascii, 1, ascii.length - 2);
s = testPattern.charAt(0) + s + testPattern.charAt(testPattern.length() - 1);
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(byte bytes[])
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, byte[].class));
s = (String) mh.invokeExact(ascii);
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
// String(StringBuffer buffer)
mh = MethodHandles.lookup().findConstructor(
String.class, MethodType.methodType(void.class, StringBuffer.class));
s = (String) mh.invokeExact(sb);
if (!s.equals(testPattern)) {
fail("Unexpected string constructor result: '" + s + "'");
}
System.out.println("String constructors done.");
}
private static void testReturnValues() throws Throwable {
Lookup lookup = MethodHandles.lookup();
// byte
MethodHandle mhByteValue =
lookup.findVirtual(Byte.class, "byteValue", MethodType.methodType(byte.class));
assertEquals((byte) -77, (byte) mhByteValue.invokeExact(Byte.valueOf((byte) -77)));
assertEquals((byte) -77, (byte) mhByteValue.invoke(Byte.valueOf((byte) -77)));
// char
MethodHandle mhCharacterValue =
lookup.findStaticGetter(Character.class, "MAX_SURROGATE", char.class);
assertEquals(Character.MAX_SURROGATE, (char) mhCharacterValue.invokeExact());
assertEquals(Character.MAX_SURROGATE, (char) mhCharacterValue.invoke());
// double
MethodHandle mhSin =
lookup.findStatic(
Math.class, "sin", MethodType.methodType(double.class, double.class));
for (double i = -Math.PI; i <= Math.PI; i += Math.PI / 8) {
assertEquals(Math.sin(i), (double) mhSin.invokeExact(i));
assertEquals(Math.sin(i), (double) mhSin.invoke(i));
}
// float
MethodHandle mhAbsFloat =
lookup.findStatic(
Math.class, "abs", MethodType.methodType(float.class, float.class));
assertEquals(Math.abs(-3.3e6f), (float) mhAbsFloat.invokeExact(-3.3e6f));
assertEquals(Math.abs(-3.3e6f), (float) mhAbsFloat.invoke(-3.3e6f));
// int
MethodHandle mhAbsInt =
lookup.findStatic(Math.class, "abs", MethodType.methodType(int.class, int.class));
assertEquals(Math.abs(-1000), (int) mhAbsInt.invokeExact(-1000));
assertEquals(Math.abs(-1000), (int) mhAbsInt.invoke(-1000));
// long
MethodHandle mhMaxLong =
lookup.findStatic(
Math.class,
"max",
MethodType.methodType(long.class, long.class, long.class));
assertEquals(
Long.MAX_VALUE, (long) mhMaxLong.invokeExact(Long.MAX_VALUE, Long.MAX_VALUE / 2));
assertEquals(Long.MAX_VALUE, (long) mhMaxLong.invoke(Long.MAX_VALUE, Long.MAX_VALUE / 2));
assertEquals(0x0123456789abcdefL, (long) mhMaxLong.invokeExact(0x0123456789abcdefL, 0L));
assertEquals(0x0123456789abcdefL, (long) mhMaxLong.invoke(0x0123456789abcdefL, 0L));
// ref
MethodHandle mhShortValueOf =
lookup.findStatic(
Short.class, "valueOf", MethodType.methodType(Short.class, short.class));
assertEquals(
(short) -7890, ((Short) mhShortValueOf.invokeExact((short) -7890)).shortValue());
assertEquals((short) -7890, ((Short) mhShortValueOf.invoke((short) -7890)).shortValue());
// array
int [] array = {Integer.MIN_VALUE, -1, 0, +1, Integer.MAX_VALUE};
MethodHandle mhCopyOf =
lookup.findStatic(
Arrays.class, "copyOf", MethodType.methodType(int[].class, int[].class, int.class));
assertTrue(Arrays.equals(array, (int[]) mhCopyOf.invokeExact(array, array.length)));
assertTrue(Arrays.equals(array, (int[]) mhCopyOf.invoke(array, array.length)));
// short
MethodHandle mhShortValue =
lookup.findVirtual(Short.class, "shortValue", MethodType.methodType(short.class));
assertEquals((short) 12131, (short) mhShortValue.invokeExact(Short.valueOf((short) 12131)));
assertEquals((short) 12131, (short) mhShortValue.invoke(Short.valueOf((short) 12131)));
// boolean
MethodHandle mhBooleanValue =
lookup.findVirtual(
Boolean.class, "booleanValue", MethodType.methodType(boolean.class));
assertEquals(true, (boolean) mhBooleanValue.invokeExact(Boolean.valueOf(true)));
assertEquals(true, (boolean) mhBooleanValue.invoke(Boolean.valueOf(true)));
assertEquals(false, (boolean) mhBooleanValue.invokeExact(Boolean.valueOf(false)));
assertEquals(false, (boolean) mhBooleanValue.invoke(Boolean.valueOf(false)));
System.out.println("testReturnValues done.");
}
private static void testReferenceReturnValueConversions() throws Throwable {
MethodHandle mh = MethodHandles.lookup().findStatic(
Float.class, "valueOf", MethodType.methodType(Float.class, String.class));
// No conversion
Float f = (Float) mh.invokeExact("1.375");
if (f.floatValue() != 1.375) {
fail();
}
f = (Float) mh.invoke("1.875");
if (f.floatValue() != 1.875) {
fail();
}
// Bad conversion
try {
int i = (int) mh.invokeExact("7.77");
fail();
} catch (WrongMethodTypeException e) {}
try {
int i = (int) mh.invoke("7.77");
fail();
} catch (WrongMethodTypeException e) {}
// Assignment to super-class.
Number n = (Number) mh.invoke("1.11");
try {
Number o = (Number) mh.invokeExact("1.11");
fail();
} catch (WrongMethodTypeException e) {}
// Assignment to widened boxed primitive class.
try {
Double u = (Double) mh.invoke("1.11");
fail();
} catch (ClassCastException e) {}
try {
Double v = (Double) mh.invokeExact("1.11");
fail();
} catch (WrongMethodTypeException e) {}
// Unboxed
float p = (float) mh.invoke("1.11");
if (p != 1.11f) {
fail();
}
// Unboxed and widened
double d = (double) mh.invoke("2.5");
if (d != 2.5) {
fail();
}
// Interface
Comparable<Float> c = (Comparable<Float>) mh.invoke("2.125");
if (c.compareTo(new Float(2.125f)) != 0) {
fail();
}
System.out.println("testReferenceReturnValueConversions done.");
}
private static void testPrimitiveReturnValueConversions() throws Throwable {
MethodHandle mh = MethodHandles.lookup().findStatic(
Math.class, "min", MethodType.methodType(int.class, int.class, int.class));
final int SMALL = -8972;
final int LARGE = 7932529;
// No conversion
if ((int) mh.invokeExact(LARGE, SMALL) != SMALL) {
fail();
} else if ((int) mh.invoke(LARGE, SMALL) != SMALL) {
fail();
} else if ((int) mh.invokeExact(SMALL, LARGE) != SMALL) {
fail();
} else if ((int) mh.invoke(SMALL, LARGE) != SMALL) {
fail();
}
// int -> long
try {
if ((long) mh.invokeExact(LARGE, SMALL) != (long) SMALL) {}
fail();
} catch (WrongMethodTypeException e) {}
if ((long) mh.invoke(LARGE, SMALL) != (long) SMALL) {
fail();
}
// int -> short
try {
if ((short) mh.invokeExact(LARGE, SMALL) != (short) SMALL) {}
fail();
} catch (WrongMethodTypeException e) {}
try {
if ((short) mh.invoke(LARGE, SMALL) != (short) SMALL) {
fail();
}
} catch (WrongMethodTypeException e) {}
// int -> Integer
try {
if (!((Integer) mh.invokeExact(LARGE, SMALL)).equals(new Integer(SMALL))) {}
fail();
} catch (WrongMethodTypeException e) {}
if (!((Integer) mh.invoke(LARGE, SMALL)).equals(new Integer(SMALL))) {
fail();
}
// int -> Long
try {
Long l = (Long) mh.invokeExact(LARGE, SMALL);
fail();
} catch (WrongMethodTypeException e) {}
try {
Long l = (Long) mh.invoke(LARGE, SMALL);
fail();
} catch (WrongMethodTypeException e) {}
// int -> Short
try {
Short s = (Short) mh.invokeExact(LARGE, SMALL);
fail();
} catch (WrongMethodTypeException e) {}
try {
Short s = (Short) mh.invoke(LARGE, SMALL);
fail();
} catch (WrongMethodTypeException e) {}
// int -> Process
try {
Process p = (Process) mh.invokeExact(LARGE, SMALL);
fail();
} catch (WrongMethodTypeException e) {}
try {
Process p = (Process) mh.invoke(LARGE, SMALL);
fail();
} catch (WrongMethodTypeException e) {}
// void -> Object
mh = MethodHandles.lookup().findStatic(System.class, "gc", MethodType.methodType(void.class));
Object o = (Object) mh.invoke();
if (o != null) fail();
// void -> long
long l = (long) mh.invoke();
if (l != 0) fail();
// boolean -> Boolean
mh = MethodHandles.lookup().findStatic(Boolean.class, "parseBoolean",
MethodType.methodType(boolean.class, String.class));
Boolean z = (Boolean) mh.invoke("True");
if (!z.booleanValue()) fail();
// boolean -> int
try {
int dummy = (int) mh.invoke("True");
fail();
} catch (WrongMethodTypeException e) {}
// boolean -> Integer
try {
Integer dummy = (Integer) mh.invoke("True");
fail();
} catch (WrongMethodTypeException e) {}
// Boolean -> boolean
mh = MethodHandles.lookup().findStatic(Boolean.class, "valueOf",
MethodType.methodType(Boolean.class, boolean.class));
boolean w = (boolean) mh.invoke(false);
if (w) fail();
// Boolean -> int
try {
int dummy = (int) mh.invoke(false);
fail();
} catch (WrongMethodTypeException e) {}
// Boolean -> Integer
try {
Integer dummy = (Integer) mh.invoke("True");
fail();
} catch (WrongMethodTypeException e) {}
System.out.println("testPrimitiveReturnValueConversions done.");
}
public static void testReturnValueConversions() throws Throwable {
testReferenceReturnValueConversions();
testPrimitiveReturnValueConversions();
}
public static class BaseVariableArityTester {
public String update(Float f0, Float... floats) {
return "base " + f0 + ", " + Arrays.toString(floats);
}
}
public static class VariableArityTester extends BaseVariableArityTester {
private String lastResult;
// Constructors
public VariableArityTester() {}
public VariableArityTester(boolean... booleans) { update(booleans); }
public VariableArityTester(byte... bytes) { update(bytes); }
public VariableArityTester(char... chars) { update(chars); }
public VariableArityTester(short... shorts) { update(shorts); }
public VariableArityTester(int... ints) { update(ints); }
public VariableArityTester(long... longs) { update(longs); }
public VariableArityTester(float... floats) { update(floats); }
public VariableArityTester(double... doubles) { update(doubles); }
public VariableArityTester(Float f0, Float... floats) { update(f0, floats); }
public VariableArityTester(String s0, String... strings) { update(s0, strings); }
public VariableArityTester(char c, Number... numbers) { update(c, numbers); }
@SafeVarargs
public VariableArityTester(ArrayList<Integer> l0, ArrayList<Integer>... lists) {
update(l0, lists);
}
public VariableArityTester(List l0, List... lists) { update(l0, lists); }
// Methods
public String update(boolean... booleans) { return lastResult = tally(booleans); }
public String update(byte... bytes) { return lastResult = tally(bytes); }
public String update(char... chars) { return lastResult = tally(chars); }
public String update(short... shorts) { return lastResult = tally(shorts); }
public String update(int... ints) {
lastResult = tally(ints);
return lastResult;
}
public String update(long... longs) { return lastResult = tally(longs); }
public String update(float... floats) { return lastResult = tally(floats); }
public String update(double... doubles) { return lastResult = tally(doubles); }
@Override
public String update(Float f0, Float... floats) { return lastResult = tally(f0, floats); }
public String update(String s0, String... strings) { return lastResult = tally(s0, strings); }
public String update(char c, Number... numbers) { return lastResult = tally(c, numbers); }
@SafeVarargs
public final String update(ArrayList<Integer> l0, ArrayList<Integer>... lists) {
lastResult = tally(l0, lists);
return lastResult;
}
public String update(List l0, List... lists) { return lastResult = tally(l0, lists); }
public String arrayMethod(Object[] o) {
return Arrays.deepToString(o);
}
public String lastResult() { return lastResult; }
// Static Methods
public static String tally(boolean... booleans) { return Arrays.toString(booleans); }
public static String tally(byte... bytes) { return Arrays.toString(bytes); }
public static String tally(char... chars) { return Arrays.toString(chars); }
public static String tally(short... shorts) { return Arrays.toString(shorts); }
public static String tally(int... ints) { return Arrays.toString(ints); }
public static String tally(long... longs) { return Arrays.toString(longs); }
public static String tally(float... floats) { return Arrays.toString(floats); }
public static String tally(double... doubles) { return Arrays.toString(doubles); }
public static String tally(Float f0, Float... floats) {
return f0 + ", " + Arrays.toString(floats);
}
public static String tally(String s0, String... strings) {
return s0 + ", " + Arrays.toString(strings);
}
public static String tally(char c, Number... numbers) {
return c + ", " + Arrays.toString(numbers);
}
@SafeVarargs
public static String tally(ArrayList<Integer> l0, ArrayList<Integer>... lists) {
return Arrays.toString(l0.toArray()) + ", " + Arrays.deepToString(lists);
}
public static String tally(List l0, List... lists) {
return Arrays.deepToString(l0.toArray()) + ", " + Arrays.deepToString(lists);
}
public static void foo(int... ints) { System.out.println(Arrays.toString(ints)); }
public static long sumToPrimitive(int... ints) {
long result = 0;
for (int i : ints) result += i;
return result;
}
public static Long sumToReference(int... ints) {
System.out.println("Hi");
return new Long(sumToPrimitive(ints));
}
public static MethodHandles.Lookup lookup() {
return MethodHandles.lookup();
}
}
// This method only exists to fool Jack's handling of types. See b/32536744.
public static Object getAsObject(String[] strings) {
return (Object) strings;
}
public static void testVariableArity() throws Throwable {
MethodHandle mh;
VariableArityTester vat = new VariableArityTester();
assertEquals("[1]", vat.update(1));
assertEquals("[1, 1]", vat.update(1, 1));
assertEquals("[1, 1, 1]", vat.update(1, 1, 1));
// Methods - boolean
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, boolean[].class));
assertTrue(mh.isVarargsCollector());
assertFalse(mh.asFixedArity().isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[true, false, true]", mh.invoke(vat, true, false, true));
assertEquals("[true, false, true]", mh.invoke(vat, new boolean[] { true, false, true}));
assertEquals("[false, true]", mh.invoke(vat, Boolean.valueOf(false), Boolean.valueOf(true)));
try {
mh.invoke(vat, true, true, 0);
fail();
} catch (WrongMethodTypeException e) {}
try {
assertEquals("[false, true]", mh.invoke(vat, Boolean.valueOf(false), (Boolean) null));
fail();
} catch (NullPointerException e) {}
// Methods - byte
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, byte[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[32, 64, 97]", mh.invoke(vat, (byte) 32, Byte.valueOf((byte) 64), (byte) 97));
assertEquals("[32, 64, 97]", mh.invoke(vat, new byte[] {(byte) 32, (byte) 64, (byte) 97}));
try {
mh.invoke(vat, (byte) 1, Integer.valueOf(3), (byte) 0);
fail();
} catch (WrongMethodTypeException e) {}
// Methods - char
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, char[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[A, B, C]", mh.invoke(vat, 'A', Character.valueOf('B'), 'C'));
assertEquals("[W, X, Y, Z]", mh.invoke(vat, new char[] { 'W', 'X', 'Y', 'Z' }));
// Methods - short
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, short[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[32767, -32768, 0]",
mh.invoke(vat, Short.MAX_VALUE, Short.MIN_VALUE, Short.valueOf((short) 0)));
assertEquals("[1, -1]", mh.invoke(vat, new short[] { (short) 1, (short) -1 }));
// Methods - int
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, int[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[0, 2147483647, -2147483648, 0]",
mh.invoke(vat, Integer.valueOf(0), Integer.MAX_VALUE, Integer.MIN_VALUE, 0));
assertEquals("[0, -1, 1, 0]", mh.invoke(vat, new int[] { 0, -1, 1, 0 }));
assertEquals("[5, 4, 3, 2, 1]", (String) mh.invokeExact(vat, new int [] { 5, 4, 3, 2, 1 }));
try {
assertEquals("[5, 4, 3, 2, 1]", (String) mh.invokeExact(vat, 5, 4, 3, 2, 1));
fail();
} catch (WrongMethodTypeException e) {}
assertEquals("[5, 4, 3, 2, 1]", (String) mh.invoke(vat, 5, 4, 3, 2, 1));
// Methods - long
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, long[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[0, 9223372036854775807, -9223372036854775808]",
mh.invoke(vat, Long.valueOf(0), Long.MAX_VALUE, Long.MIN_VALUE));
assertEquals("[0, -1, 1, 0]", mh.invoke(vat, new long[] { 0, -1, 1, 0 }));
// Methods - float
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, float[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[0.0, 1.25, -1.25]",
mh.invoke(vat, 0.0f, Float.valueOf(1.25f), Float.valueOf(-1.25f)));
assertEquals("[0.0, -1.0, 1.0, 0.0]",
mh.invoke(vat, new float[] { 0.0f, -1.0f, 1.0f, 0.0f }));
// Methods - double
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, double[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke(vat));
assertEquals("[0.0, 1.25, -1.25]",
mh.invoke(vat, 0.0, Double.valueOf(1.25), Double.valueOf(-1.25)));
assertEquals("[0.0, -1.0, 1.0, 0.0]",
mh.invoke(vat, new double[] { 0.0, -1.0, 1.0, 0.0 }));
mh.invoke(vat, 0.3f, 1.33, 1.33);
// Methods - String
mh = MethodHandles.lookup().
findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, String.class, String[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("Echidna, []", mh.invoke(vat, "Echidna"));
assertEquals("Bongo, [Jerboa, Okapi]",
mh.invoke(vat, "Bongo", "Jerboa", "Okapi"));
// Methods - Float
mh = MethodHandles.lookup().
findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, Float.class, Float[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(vat, Float.valueOf(9.99f),
new Float[] { Float.valueOf(0.0f),
Float.valueOf(0.1f),
Float.valueOf(1.1f) }));
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(vat, Float.valueOf(9.99f), Float.valueOf(0.0f),
Float.valueOf(0.1f), Float.valueOf(1.1f)));
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(vat, Float.valueOf(9.99f), 0.0f, 0.1f, 1.1f));
try {
assertEquals("9.99, [77.0, 33.0, 64.0]",
(String) mh.invoke(vat, Float.valueOf(9.99f), 77, 33, 64));
fail();
} catch (WrongMethodTypeException e) {}
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invokeExact(vat, Float.valueOf(9.99f),
new Float[] { Float.valueOf(0.0f),
Float.valueOf(0.1f),
Float.valueOf(1.1f) }));
assertEquals("9.99, [0.0, null, 1.1]",
(String) mh.invokeExact(vat, Float.valueOf(9.99f),
new Float[] { Float.valueOf(0.0f),
null,
Float.valueOf(1.1f) }));
try {
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invokeExact(vat, Float.valueOf(9.99f), 0.0f, 0.1f, 1.1f));
fail();
} catch (WrongMethodTypeException e) {}
// Methods - Number
mh = MethodHandles.lookup().
findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, char.class, Number[].class));
assertTrue(mh.isVarargsCollector());
assertFalse(mh.asFixedArity().isVarargsCollector());
assertEquals("x, []", (String) mh.invoke(vat, 'x'));
assertEquals("x, [3.141]", (String) mh.invoke(vat, 'x', 3.141));
assertEquals("x, [null, 3.131, 37]",
(String) mh.invoke(vat, 'x', null, 3.131, new Integer(37)));
try {
assertEquals("x, [null, 3.131, bad, 37]",
(String) mh.invoke(vat, 'x', null, 3.131, "bad", new Integer(37)));
assertTrue(false);
fail();
} catch (ClassCastException e) {}
try {
assertEquals("x, [null, 3.131, bad, 37]",
(String) mh.invoke(
vat, 'x', (Process) null, 3.131, "bad", new Integer(37)));
assertTrue(false);
fail();
} catch (ClassCastException e) {}
// Methods - an array method that is not variable arity.
mh = MethodHandles.lookup().findVirtual(
VariableArityTester.class, "arrayMethod",
MethodType.methodType(String.class, Object[].class));
assertFalse(mh.isVarargsCollector());
mh.invoke(vat, new Object[] { "123" });
try {
assertEquals("-", mh.invoke(vat, new Float(3), new Float(4)));
fail();
} catch (WrongMethodTypeException e) {}
mh = mh.asVarargsCollector(Object[].class);
assertTrue(mh.isVarargsCollector());
assertEquals("[3.0, 4.0]", (String) mh.invoke(vat, new Float(3), new Float(4)));
// Constructors - default
mh = MethodHandles.lookup().findConstructor(
VariableArityTester.class, MethodType.methodType(void.class));
assertFalse(mh.isVarargsCollector());
// Constructors - boolean
mh = MethodHandles.lookup().findConstructor(
VariableArityTester.class, MethodType.methodType(void.class, boolean[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[true, true, false]",
((VariableArityTester) mh.invoke(new boolean[] {true, true, false})).lastResult());
assertEquals("[true, true, false]",
((VariableArityTester) mh.invoke(true, true, false)).lastResult());
try {
assertEquals("[true, true, false]",
((VariableArityTester) mh.invokeExact(true, true, false)).lastResult());
fail();
} catch (WrongMethodTypeException e) {}
// Constructors - byte
mh = MethodHandles.lookup().findConstructor(
VariableArityTester.class, MethodType.methodType(void.class, byte[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[55, 66, 60]",
((VariableArityTester)
mh.invoke(new byte[] {(byte) 55, (byte) 66, (byte) 60})).lastResult());
assertEquals("[55, 66, 60]",
((VariableArityTester) mh.invoke(
(byte) 55, (byte) 66, (byte) 60)).lastResult());
try {
assertEquals("[55, 66, 60]",
((VariableArityTester) mh.invokeExact(
(byte) 55, (byte) 66, (byte) 60)).lastResult());
fail();
} catch (WrongMethodTypeException e) {}
try {
assertEquals("[3, 3]",
((VariableArityTester) mh.invoke(
new Number[] { Byte.valueOf((byte) 3), (byte) 3})).lastResult());
fail();
} catch (WrongMethodTypeException e) {}
// Constructors - String (have a different path than other reference types).
mh = MethodHandles.lookup().findConstructor(
VariableArityTester.class, MethodType.methodType(void.class, String.class, String[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("x, []", ((VariableArityTester) mh.invoke("x")).lastResult());
assertEquals("x, [y]", ((VariableArityTester) mh.invoke("x", "y")).lastResult());
assertEquals("x, [y, z]",
((VariableArityTester) mh.invoke("x", new String[] { "y", "z" })).lastResult());
try {
assertEquals("x, [y]", ((VariableArityTester) mh.invokeExact("x", "y")).lastResult());
fail();
} catch (WrongMethodTypeException e) {}
assertEquals("x, [null, z]",
((VariableArityTester) mh.invoke("x", new String[] { null, "z" })).lastResult());
// Constructors - Number
mh = MethodHandles.lookup().findConstructor(
VariableArityTester.class, MethodType.methodType(void.class, char.class, Number[].class));
assertTrue(mh.isVarargsCollector());
assertFalse(mh.asFixedArity().isVarargsCollector());
assertEquals("x, []", ((VariableArityTester) mh.invoke('x')).lastResult());
assertEquals("x, [3.141]", ((VariableArityTester) mh.invoke('x', 3.141)).lastResult());
assertEquals("x, [null, 3.131, 37]",
((VariableArityTester) mh.invoke('x', null, 3.131, new Integer(37))).lastResult());
try {
assertEquals("x, [null, 3.131, bad, 37]",
((VariableArityTester) mh.invoke(
'x', null, 3.131, "bad", new Integer(37))).lastResult());
assertTrue(false);
fail();
} catch (ClassCastException e) {}
try {
assertEquals("x, [null, 3.131, bad, 37]",
((VariableArityTester) mh.invoke(
'x', (Process) null, 3.131, "bad", new Integer(37))).lastResult());
assertTrue(false);
fail();
} catch (ClassCastException e) {}
// Static Methods - Float
mh = MethodHandles.lookup().
findStatic(VariableArityTester.class, "tally",
MethodType.methodType(String.class, Float.class, Float[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(Float.valueOf(9.99f),
new Float[] { Float.valueOf(0.0f),
Float.valueOf(0.1f),
Float.valueOf(1.1f) }));
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(Float.valueOf(9.99f), Float.valueOf(0.0f),
Float.valueOf(0.1f), Float.valueOf(1.1f)));
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(Float.valueOf(9.99f), 0.0f, 0.1f, 1.1f));
try {
assertEquals("9.99, [77.0, 33.0, 64.0]",
(String) mh.invoke(Float.valueOf(9.99f), 77, 33, 64));
fail();
} catch (WrongMethodTypeException e) {}
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invokeExact(Float.valueOf(9.99f),
new Float[] { Float.valueOf(0.0f),
Float.valueOf(0.1f),
Float.valueOf(1.1f) }));
assertEquals("9.99, [0.0, null, 1.1]",
(String) mh.invokeExact(Float.valueOf(9.99f),
new Float[] { Float.valueOf(0.0f),
null,
Float.valueOf(1.1f) }));
try {
assertEquals("9.99, [0.0, 0.1, 1.1]",
(String) mh.invokeExact(Float.valueOf(9.99f), 0.0f, 0.1f, 1.1f));
fail();
} catch (WrongMethodTypeException e) {}
// Special methods - Float
mh = VariableArityTester.lookup().
findSpecial(BaseVariableArityTester.class, "update",
MethodType.methodType(String.class, Float.class, Float[].class),
VariableArityTester.class);
assertTrue(mh.isVarargsCollector());
assertEquals("base 9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(vat,
Float.valueOf(9.99f),
new Float[] { Float.valueOf(0.0f),
Float.valueOf(0.1f),
Float.valueOf(1.1f) }));
assertEquals("base 9.99, [0.0, 0.1, 1.1]",
(String) mh.invoke(vat, Float.valueOf(9.99f), Float.valueOf(0.0f),
Float.valueOf(0.1f), Float.valueOf(1.1f)));
// Return value conversions.
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, int[].class));
assertEquals("[1, 2, 3]", (String) mh.invoke(vat, 1, 2, 3));
assertEquals("[1, 2, 3]", (Object) mh.invoke(vat, 1, 2, 3));
try {
assertEquals("[1, 2, 3, 4]", (long) mh.invoke(vat, 1, 2, 3));
fail();
} catch (WrongMethodTypeException e) {}
assertEquals("[1, 2, 3]", vat.lastResult());
mh = MethodHandles.lookup().findStatic(VariableArityTester.class, "sumToPrimitive",
MethodType.methodType(long.class, int[].class));
assertEquals(10l, (long) mh.invoke(1, 2, 3, 4));
assertEquals(Long.valueOf(10l), (Long) mh.invoke(1, 2, 3, 4));
mh = MethodHandles.lookup().findStatic(VariableArityTester.class, "sumToReference",
MethodType.methodType(Long.class, int[].class));
Object o = mh.invoke(1, 2, 3, 4);
long l = (long) mh.invoke(1, 2, 3, 4);
assertEquals(10l, (long) mh.invoke(1, 2, 3, 4));
assertEquals(Long.valueOf(10l), (Long) mh.invoke(1, 2, 3, 4));
try {
// WrongMethodTypeException should be raised before invoke here.
System.out.print("Expect Hi here: ");
assertEquals(Long.valueOf(10l), (Byte) mh.invoke(1, 2, 3, 4));
fail();
} catch (ClassCastException e) {}
try {
// WrongMethodTypeException should be raised before invoke here.
System.out.println("Don't expect Hi now");
byte b = (byte) mh.invoke(1, 2, 3, 4);
fail();
} catch (WrongMethodTypeException e) {}
// Return void produces 0 / null.
mh = MethodHandles.lookup().findStatic(VariableArityTester.class, "foo",
MethodType.methodType(void.class, int[].class));
assertEquals(null, (Object) mh.invoke(3, 2, 1));
assertEquals(0l, (long) mh.invoke(1, 2, 3));
// Combinators
mh = MethodHandles.lookup().findVirtual(VariableArityTester.class, "update",
MethodType.methodType(String.class, boolean[].class));
assertTrue(mh.isVarargsCollector());
mh = mh.bindTo(vat);
assertFalse(mh.isVarargsCollector());
mh = mh.asVarargsCollector(boolean[].class);
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke());
assertEquals("[true, false, true]", mh.invoke(true, false, true));
assertEquals("[true, false, true]", mh.invoke(new boolean[] { true, false, true}));
assertEquals("[false, true]", mh.invoke(Boolean.valueOf(false), Boolean.valueOf(true)));
try {
mh.invoke(true, true, 0);
fail();
} catch (WrongMethodTypeException e) {}
}
// The same tests as the above, except that we use use MethodHandles.bind instead of
// MethodHandle.bindTo.
public static void testVariableArity_MethodHandles_bind() throws Throwable {
VariableArityTester vat = new VariableArityTester();
MethodHandle mh = MethodHandles.lookup().bind(vat, "update",
MethodType.methodType(String.class, boolean[].class));
assertTrue(mh.isVarargsCollector());
assertEquals("[]", mh.invoke());
assertEquals("[true, false, true]", mh.invoke(true, false, true));
assertEquals("[true, false, true]", mh.invoke(new boolean[] { true, false, true}));
assertEquals("[false, true]", mh.invoke(Boolean.valueOf(false), Boolean.valueOf(true)));
try {
mh.invoke(true, true, 0);
fail();
} catch (WrongMethodTypeException e) {}
}
public static void testRevealDirect() throws Throwable {
// Test with a virtual method :
MethodType type = MethodType.methodType(String.class);
MethodHandle handle = MethodHandles.lookup().findVirtual(
UnreflectTester.class, "publicMethod", type);
// Comparisons with an equivalent member obtained via reflection :
MethodHandleInfo info = MethodHandles.lookup().revealDirect(handle);
Method meth = UnreflectTester.class.getMethod("publicMethod");
assertEquals(MethodHandleInfo.REF_invokeVirtual, info.getReferenceKind());
assertEquals("publicMethod", info.getName());
assertTrue(UnreflectTester.class == info.getDeclaringClass());
assertFalse(info.isVarArgs());
assertEquals(meth, info.reflectAs(Method.class, MethodHandles.lookup()));
assertEquals(type, info.getMethodType());
// Resolution via a public lookup should fail because the method in question
// isn't public.
try {
info.reflectAs(Method.class, MethodHandles.publicLookup());
fail();
} catch (IllegalArgumentException expected) {
}
// Test with a static method :
handle = MethodHandles.lookup().findStatic(UnreflectTester.class,
"publicStaticMethod",
MethodType.methodType(String.class));
info = MethodHandles.lookup().revealDirect(handle);
meth = UnreflectTester.class.getMethod("publicStaticMethod");
assertEquals(MethodHandleInfo.REF_invokeStatic, info.getReferenceKind());
assertEquals("publicStaticMethod", info.getName());
assertTrue(UnreflectTester.class == info.getDeclaringClass());
assertFalse(info.isVarArgs());
assertEquals(meth, info.reflectAs(Method.class, MethodHandles.lookup()));
assertEquals(type, info.getMethodType());
// Test with a var-args method :
type = MethodType.methodType(String.class, String[].class);
handle = MethodHandles.lookup().findVirtual(UnreflectTester.class,
"publicVarArgsMethod", type);
info = MethodHandles.lookup().revealDirect(handle);
meth = UnreflectTester.class.getMethod("publicVarArgsMethod", String[].class);
assertEquals(MethodHandleInfo.REF_invokeVirtual, info.getReferenceKind());
assertEquals("publicVarArgsMethod", info.getName());
assertTrue(UnreflectTester.class == info.getDeclaringClass());
assertTrue(info.isVarArgs());
assertEquals(meth, info.reflectAs(Method.class, MethodHandles.lookup()));
assertEquals(type, info.getMethodType());
// Test with a constructor :
Constructor cons = UnreflectTester.class.getConstructor(String.class, boolean.class);
type = MethodType.methodType(void.class, String.class, boolean.class);
handle = MethodHandles.lookup().findConstructor(UnreflectTester.class, type);
info = MethodHandles.lookup().revealDirect(handle);
assertEquals(MethodHandleInfo.REF_newInvokeSpecial, info.getReferenceKind());
assertEquals("<init>", info.getName());
assertTrue(UnreflectTester.class == info.getDeclaringClass());
assertFalse(info.isVarArgs());
assertEquals(cons, info.reflectAs(Constructor.class, MethodHandles.lookup()));
assertEquals(type, info.getMethodType());
// Test with a static field :
Field field = UnreflectTester.class.getField("publicStaticField");
handle = MethodHandles.lookup().findStaticSetter(
UnreflectTester.class, "publicStaticField", String.class);
info = MethodHandles.lookup().revealDirect(handle);
assertEquals(MethodHandleInfo.REF_putStatic, info.getReferenceKind());
assertEquals("publicStaticField", info.getName());
assertTrue(UnreflectTester.class == info.getDeclaringClass());
assertFalse(info.isVarArgs());
assertEquals(field, info.reflectAs(Field.class, MethodHandles.lookup()));
assertEquals(MethodType.methodType(void.class, String.class), info.getMethodType());
// Test with a setter on the same field, the type of the handle should change
// but everything else must remain the same.
handle = MethodHandles.lookup().findStaticGetter(
UnreflectTester.class, "publicStaticField", String.class);
info = MethodHandles.lookup().revealDirect(handle);
assertEquals(MethodHandleInfo.REF_getStatic, info.getReferenceKind());
assertEquals(field, info.reflectAs(Field.class, MethodHandles.lookup()));
assertEquals(MethodType.methodType(String.class), info.getMethodType());
// Test with an instance field :
field = UnreflectTester.class.getField("publicField");
handle = MethodHandles.lookup().findSetter(
UnreflectTester.class, "publicField", String.class);
info = MethodHandles.lookup().revealDirect(handle);
assertEquals(MethodHandleInfo.REF_putField, info.getReferenceKind());
assertEquals("publicField", info.getName());
assertTrue(UnreflectTester.class == info.getDeclaringClass());
assertFalse(info.isVarArgs());
assertEquals(field, info.reflectAs(Field.class, MethodHandles.lookup()));
assertEquals(MethodType.methodType(void.class, String.class), info.getMethodType());
// Test with a setter on the same field, the type of the handle should change
// but everything else must remain the same.
handle = MethodHandles.lookup().findGetter(
UnreflectTester.class, "publicField", String.class);
info = MethodHandles.lookup().revealDirect(handle);
assertEquals(MethodHandleInfo.REF_getField, info.getReferenceKind());
assertEquals(field, info.reflectAs(Field.class, MethodHandles.lookup()));
assertEquals(MethodType.methodType(String.class), info.getMethodType());
}
public static void testReflectiveCalls() throws Throwable {
String[] methodNames = { "invoke", "invokeExact" };
for (String methodName : methodNames) {
Method invokeMethod = MethodHandle.class.getMethod(methodName, Object[].class);
MethodHandle instance =
MethodHandles.lookup().findVirtual(java.io.PrintStream.class, "println",
MethodType.methodType(void.class, String.class));
try {
invokeMethod.invoke(instance, new Object[] { new Object[] { Integer.valueOf(1) } } );
fail();
} catch (InvocationTargetException ite) {
assertEquals(ite.getCause().getClass(), UnsupportedOperationException.class);
}
}
}
public static void testInterfaceSpecial() throws Throwable {
final Method acceptMethod = Consumer.class.getDeclaredMethod("accept", Object.class);
final Method andThenMethod = Consumer.class.getDeclaredMethod("andThen", Consumer.class);
// Proxies
Consumer<Object> c = (Consumer<Object>)Proxy.newProxyInstance(
Main.class.getClassLoader(),
new Class<?>[] { Consumer.class },
(p, m, a) -> {
System.out.println("Trying to call " + m);
if (m.equals(andThenMethod)) {
List<Object> args = a == null ? Collections.EMPTY_LIST : Arrays.asList(a);
return MethodHandles.lookup()
.findSpecial(Consumer.class,
m.getName(),
MethodType.methodType(m.getReturnType(),
m.getParameterTypes()),
p.getClass())
.bindTo(p)
.invokeWithArguments(args);
} else if (m.equals(acceptMethod)) {
System.out.println("Called accept with " + a[0]);
}
return null;
});
c.accept("foo");
Consumer<Object> c2 = c.andThen((Object o) -> { System.out.println("and then " + o); });
c2.accept("bar");
// Non-proxies
Consumer<Object> c3 = new Consumer() {
public void accept(Object o) {
System.out.println("Got " + o);
}
@Override
public Consumer<Object> andThen(Consumer c) {
System.out.println("Ignoring and then");
return this;
}
};
Consumer<Object> c4 = c3.andThen((x) -> { throw new Error("Failed"); });
c4.accept("hello");
Consumer<Object> andthen = (Object o) -> { System.out.println("Called and then with " + o);};
Consumer<Object> c5 =
(Consumer<Object>)MethodHandles.lookup()
.findSpecial(Consumer.class,
andThenMethod.getName(),
MethodType.methodType(
andThenMethod.getReturnType(),
andThenMethod.getParameterTypes()),
c3.getClass())
.bindTo(c3)
.invoke(andthen);
c5.accept("hello there");
// Failures
MethodHandle abstract_target =
MethodHandles.lookup()
.findSpecial(Consumer.class,
acceptMethod.getName(),
MethodType.methodType(acceptMethod.getReturnType(),
acceptMethod.getParameterTypes()),
c3.getClass());
try {
abstract_target.invoke(c3, "hello");
} catch (IllegalAccessException e) {
System.out.println("Got expected IAE when invoke-special on an abstract interface method");
}
}
}