java.lang.invoke.MethodHandles#constant ( )源码实例Demo

下面列出了java.lang.invoke.MethodHandles#constant ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。

源代码1 项目： openjdk-jdk9 文件： LoopCombinatorTest.java

@DataProvider
static Object[][] countedLoopNegativeData() {
    MethodHandle dummy = MethodHandles.zero(void.class);
    MethodHandle one = MethodHandles.constant(int.class, 1);
    MethodHandle oneString = MethodHandles.dropArguments(one, 0, String.class);
    MethodHandle oneDouble = MethodHandles.dropArguments(one, 0, double.class);
    return new Object[][]{
            {dummy, one, dummy, dummy, String.format("start/end must return int %s, %s", dummy, one)},
            {one, dummy, dummy, dummy, String.format("start/end must return int %s, %s", one, dummy)},
            {oneString, oneDouble, dummy, dummy,
                    String.format("start and end parameter types must match: %s != %s", oneString.type(),
                            oneDouble.type())},
            {oneString, oneString, dummy, dummy,
                    String.format("start/end and init parameter types must match: %s != %s", oneString.type(),
                            dummy.type())},
            {one, one, null, dummy, String.format("actual and expected body signatures must match: %s != %s",
                    dummy.type(), dummy.type().appendParameterTypes(int.class))}
    };
}

源代码2 项目： groovy 文件： Selector.java

private void handleBoolean() {
    if (handle != null) return;

    // boolean->boolean, Boolean->boolean, boolean->Boolean
    // is handled by compiler
    // that leaves (T)Z and (T)Boolean, where T is the static type
    // but runtime type of T might be Boolean

    boolean primitive = staticTargetType == boolean.class;
    if (!primitive && staticTargetType != Boolean.class) return;
    if (args[0] == null) {
        if (primitive) {
            handle = MethodHandles.constant(boolean.class, false);
            handle = MethodHandles.dropArguments(handle, 0, staticSourceType);
        } else {
            handle = BOOLEAN_IDENTITY;
        }
    } else if (args[0] instanceof Boolean) {
        // give value through or unbox
        handle = BOOLEAN_IDENTITY;
    } else {
        //call asBoolean
        name = "asBoolean";
        super.setCallSiteTarget();
    }
}

源代码3 项目： hottub 文件： ExplicitCastArgumentsTest.java

/**
 * Tests that MHs.eCA method works correctly with MHs with multiple arguments.
 * @throws Throwable
 */
public static void testMultipleArgs() throws Throwable {
    int arity = 1 + RNG.nextInt(Helper.MAX_ARITY / 2 - 2);
    int arityMinus = RNG.nextInt(arity);
    int arityPlus = arity + RNG.nextInt(Helper.MAX_ARITY / 2 - arity) + 1;
    MethodType mType = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNew = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNewMinus = Helper.randomMethodTypeGenerator(arityMinus);
    MethodType mTypeNewPlus = Helper.randomMethodTypeGenerator(arityPlus);
    Class<?> rType = mType.returnType();
    MethodHandle original;
    if (rType.equals(void.class)) {
        MethodType mt = MethodType.methodType(void.class);
        original = MethodHandles.publicLookup()
                .findStatic(THIS_CLASS, "retVoid", mt);
    } else {
        Object rValue = Helper.castToWrapper(1, rType);
        original = MethodHandles.constant(rType, rValue);
    }
    original = Helper.addTrailingArgs(original, arity, mType.parameterList());
    MethodHandle target = MethodHandles
                .explicitCastArguments(original, mTypeNew);
    Object[] parList = Helper.randomArgs(mTypeNew.parameterList());
    for (int i = 0; i < parList.length; i++) {
        if (parList[i] instanceof String) {
            parList[i] = null; //getting rid of Stings produced by randomArgs
        }
    }
    target.invokeWithArguments(parList);
    checkForWrongMethodTypeException(original, mTypeNewMinus);
    checkForWrongMethodTypeException(original, mTypeNewPlus);
}

源代码4 项目： dragonwell8_jdk 文件： MethodHandlesProxiesTest.java

@Test
    public static void testOverriddenDefaultMethods() throws Throwable {
    MethodHandle target = MethodHandles.constant(String.class, "F");
    Override proxy = MethodHandleProxies.asInterfaceInstance(Override.class, target);

    assertEquals(proxy.a(), "OA");
    assertEquals(proxy.b(), "OB");
    assertEquals(proxy.c(), "OC");
}

源代码5 项目： TencentKona-8 文件： ExplicitCastArgumentsTest.java

/**
 * Tests that MHs.eCA method works correctly with MHs with multiple arguments.
 * @throws Throwable
 */
public static void testMultipleArgs() throws Throwable {
    int arity = 1 + RNG.nextInt(Helper.MAX_ARITY / 2 - 2);
    int arityMinus = RNG.nextInt(arity);
    int arityPlus = arity + RNG.nextInt(Helper.MAX_ARITY / 2 - arity) + 1;
    MethodType mType = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNew = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNewMinus = Helper.randomMethodTypeGenerator(arityMinus);
    MethodType mTypeNewPlus = Helper.randomMethodTypeGenerator(arityPlus);
    Class<?> rType = mType.returnType();
    MethodHandle original;
    if (rType.equals(void.class)) {
        MethodType mt = MethodType.methodType(void.class);
        original = MethodHandles.publicLookup()
                .findStatic(THIS_CLASS, "retVoid", mt);
    } else {
        Object rValue = Helper.castToWrapper(1, rType);
        original = MethodHandles.constant(rType, rValue);
    }
    original = Helper.addTrailingArgs(original, arity, mType.parameterList());
    MethodHandle target = MethodHandles
                .explicitCastArguments(original, mTypeNew);
    Object[] parList = Helper.randomArgs(mTypeNew.parameterList());
    for (int i = 0; i < parList.length; i++) {
        if (parList[i] instanceof String) {
            parList[i] = null; //getting rid of Stings produced by randomArgs
        }
    }
    target.invokeWithArguments(parList);
    checkForWrongMethodTypeException(original, mTypeNewMinus);
    checkForWrongMethodTypeException(original, mTypeNewPlus);
}

源代码6 项目： openjdk-jdk9 文件： LoopCombinatorTest.java

@Test
public static void testCountedLoopCounterInit() throws Throwable {
    // int x = 0; for (int i = 0; i < 5; ++i) { x += i; } return x; => 10
    // (only if counter's first value in body is 0)
    MethodHandle iter = MethodHandles.constant(int.class, 5);
    MethodHandle init = MethodHandles.constant(int.class, 0);
    MethodHandle body = Counted.MH_addCounter;
    MethodHandle loop = MethodHandles.countedLoop(iter, init, body);
    assertEquals(Counted.MT_counterInit, loop.type());
    assertEquals(10, loop.invoke());
}

源代码7 项目： TencentKona-8 文件： MethodHandlesProxiesTest.java

@Test
    public static void testOverriddenDefaultMethods() throws Throwable {
    MethodHandle target = MethodHandles.constant(String.class, "F");
    Override proxy = MethodHandleProxies.asInterfaceInstance(Override.class, target);

    assertEquals(proxy.a(), "OA");
    assertEquals(proxy.b(), "OB");
    assertEquals(proxy.c(), "OC");
}

源代码8 项目： openjdk-jdk9 文件： WrapperTest.java

@Test
public void testCharacterZeroConversion() throws Throwable {
    MethodHandle h1 = MethodHandles.constant(Character.class, (char)42);
    MethodHandle h2 = h1.asType(MethodType.methodType(void.class));  // drop 42
    MethodHandle h3 = h2.asType(MethodType.methodType(char.class));  // add 0
    MethodHandle h4 = h3.asType(MethodType.methodType(Object.class));  // box

    Object x = h4.invokeExact();
    assertEquals(x, (char)0);
    assertTrue(x == Character.valueOf((char)0));
    assertTrue(x == Wrapper.CHAR.zero());
}

源代码9 项目： openjdk-jdk8u 文件： MethodHandlesProxiesTest.java

@Test
    public static void testOverriddenDefaultMethods() throws Throwable {
    MethodHandle target = MethodHandles.constant(String.class, "F");
    Override proxy = MethodHandleProxies.asInterfaceInstance(Override.class, target);

    assertEquals(proxy.a(), "OA");
    assertEquals(proxy.b(), "OB");
    assertEquals(proxy.c(), "OC");
}

源代码10 项目： openjdk-jdk9 文件： WrapperTest.java

@Test
public void testByteZeroConversion() throws Throwable {
    MethodHandle h1 = MethodHandles.constant(Byte.class, (byte)42);
    MethodHandle h2 = h1.asType(MethodType.methodType(void.class));  // drop 42
    MethodHandle h3 = h2.asType(MethodType.methodType(byte.class));  // add 0
    MethodHandle h4 = h3.asType(MethodType.methodType(Object.class));  // box

    Object x = h4.invokeExact();
    assertEquals(x, (byte)0);
    assertTrue(x == Byte.valueOf((byte)0));
    assertTrue(x == Wrapper.BYTE.zero());
}

源代码11 项目： openjdk-jdk9 文件： WrapperTest.java

@Test
public void testShortZeroConversion() throws Throwable {
    MethodHandle h1 = MethodHandles.constant(Short.class, (short)42);
    MethodHandle h2 = h1.asType(MethodType.methodType(void.class));  // drop 42
    MethodHandle h3 = h2.asType(MethodType.methodType(short.class));  // add 0
    MethodHandle h4 = h3.asType(MethodType.methodType(Object.class));  // box

    Object x = h4.invokeExact();
    assertEquals(x, (short)0);
    assertTrue(x == Short.valueOf((short)0));
    assertTrue(x == Wrapper.SHORT.zero());
}

源代码12 项目： jdk8u_jdk 文件： ExplicitCastArgumentsTest.java

/**
 * Tests that MHs.eCA method works correctly with MHs with multiple arguments.
 * @throws Throwable
 */
public static void testMultipleArgs() throws Throwable {
    int arity = 1 + RNG.nextInt(Helper.MAX_ARITY / 2 - 2);
    int arityMinus = RNG.nextInt(arity);
    int arityPlus = arity + RNG.nextInt(Helper.MAX_ARITY / 2 - arity) + 1;
    MethodType mType = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNew = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNewMinus = Helper.randomMethodTypeGenerator(arityMinus);
    MethodType mTypeNewPlus = Helper.randomMethodTypeGenerator(arityPlus);
    Class<?> rType = mType.returnType();
    MethodHandle original;
    if (rType.equals(void.class)) {
        MethodType mt = MethodType.methodType(void.class);
        original = MethodHandles.publicLookup()
                .findStatic(THIS_CLASS, "retVoid", mt);
    } else {
        Object rValue = Helper.castToWrapper(1, rType);
        original = MethodHandles.constant(rType, rValue);
    }
    original = Helper.addTrailingArgs(original, arity, mType.parameterList());
    MethodHandle target = MethodHandles
                .explicitCastArguments(original, mTypeNew);
    Object[] parList = Helper.randomArgs(mTypeNew.parameterList());
    for (int i = 0; i < parList.length; i++) {
        if (parList[i] instanceof String) {
            parList[i] = null; //getting rid of Stings produced by randomArgs
        }
    }
    target.invokeWithArguments(parList);
    checkForWrongMethodTypeException(original, mTypeNewMinus);
    checkForWrongMethodTypeException(original, mTypeNewPlus);
}

源代码13 项目： openjdk-jdk9 文件： WrapperTest.java

@Test
public void testIntZeroConversion() throws Throwable {
    MethodHandle h1 = MethodHandles.constant(Integer.class, 42);
    MethodHandle h2 = h1.asType(MethodType.methodType(void.class));  // drop 42
    MethodHandle h3 = h2.asType(MethodType.methodType(int.class));  // add 0
    MethodHandle h4 = h3.asType(MethodType.methodType(Object.class));  // box

    Object x = h4.invokeExact();
    assertEquals(x, 0);
    assertTrue(x == Integer.valueOf(0));
    assertTrue(x == Wrapper.INT.zero());
}

源代码14 项目： openjdk-jdk9 文件： ExplicitCastArgumentsTest.java

/**
 * Tests that MHs.eCA method works correctly with MHs with multiple arguments.
 * @throws Throwable
 */
public static void testMultipleArgs() throws Throwable {
    int arity = 1 + RNG.nextInt(Helper.MAX_ARITY / 2 - 2);
    int arityMinus = RNG.nextInt(arity);
    int arityPlus = arity + RNG.nextInt(Helper.MAX_ARITY / 2 - arity) + 1;
    MethodType mType = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNew = Helper.randomMethodTypeGenerator(arity);
    MethodType mTypeNewMinus = Helper.randomMethodTypeGenerator(arityMinus);
    MethodType mTypeNewPlus = Helper.randomMethodTypeGenerator(arityPlus);
    Class<?> rType = mType.returnType();
    MethodHandle original;
    if (rType.equals(void.class)) {
        MethodType mt = MethodType.methodType(void.class);
        original = MethodHandles.publicLookup()
                .findStatic(THIS_CLASS, "retVoid", mt);
    } else {
        Object rValue = Helper.castToWrapper(1, rType);
        original = MethodHandles.constant(rType, rValue);
    }
    original = Helper.addTrailingArgs(original, arity, mType.parameterList());
    MethodHandle target = MethodHandles
                .explicitCastArguments(original, mTypeNew);
    Object[] parList = Helper.randomArgs(mTypeNew.parameterList());
    for (int i = 0; i < parList.length; i++) {
        if (parList[i] instanceof String) {
            parList[i] = null; //getting rid of Stings produced by randomArgs
        }
    }
    target.invokeWithArguments(parList);
    checkForWrongMethodTypeException(original, mTypeNewMinus);
    checkForWrongMethodTypeException(original, mTypeNewPlus);
}

源代码15 项目： nashorn 文件： MethodHandleFactory.java

@Override
public MethodHandle constant(final Class<?> type, final Object value) {
    return MethodHandles.constant(type, value);
}

源代码16 项目： TencentKona-8 文件： MethodHandleFactory.java

@Override
public MethodHandle constant(final Class<?> type, final Object value) {
    final MethodHandle mh = MethodHandles.constant(type, value);
    return debug(mh, "constant", type, value);
}

源代码17 项目： openjdk-jdk8u 文件： MethodHandleFactory.java

@Override
public MethodHandle constant(final Class<?> type, final Object value) {
    final MethodHandle mh = MethodHandles.constant(type, value);
    return debug(mh, "constant", type, value);
}

源代码18 项目： openjdk-jdk8u-backup 文件： MethodHandleFactory.java

@Override
public MethodHandle constant(final Class<?> type, final Object value) {
    final MethodHandle mh = MethodHandles.constant(type, value);
    return debug(mh, "constant", type, value);
}

源代码19 项目： openjdk-8 文件： MethodHandleFactory.java

@Override
public MethodHandle constant(final Class<?> type, final Object value) {
    return MethodHandles.constant(type, value);
}

源代码20 项目： openjdk-jdk9 文件： LoopCombinatorTest.java

@DataProvider
static Object[][] nullArgs() {
    MethodHandle c = MethodHandles.constant(int.class, 1);
    return new Object[][]{{null, c}, {c, null}};
}