Examples of java.lang.invoke.MethodHandle.invoke()

java.lang.invoke.MethodHandle.invoke()
Invokes the method handle, allowing any caller type descriptor, and optionally performing conversions on arguments and return values.
If the call site's symbolic type descriptor exactly matches this method handle's {@link #type type}, the call proceeds as if by {@link #invokeExact invokeExact}.
Otherwise, the call proceeds as if this method handle were first adjusted by calling {@link #asType asType} to adjust this method handleto the required type, and then the call proceeds as if by {@link #invokeExact invokeExact} on the adjusted method handle.
There is no guarantee that the {@code asType} call is actually made.If the JVM can predict the results of making the call, it may perform adaptations directly on the caller's arguments, and call the target method handle according to its own exact type.
The resolved type descriptor at the call site of {@code invoke} mustbe a valid argument to the receivers {@code asType} method.In particular, the caller must specify the same argument arity as the callee's type, if the callee is not a {@linkplain #asVarargsCollector variable arity collector}.
When this method is observed via the Core Reflection API, it will appear as a single native method, taking an object array and returning an object. If this native method is invoked directly via {@link java.lang.reflect.Method#invoke java.lang.reflect.Method.invoke}, via JNI, or indirectly via {@link java.lang.invoke.MethodHandles.Lookup#unreflect Lookup.unreflect}, it will throw an {@code UnsupportedOperationException}. @param args the signature-polymorphic parameter list, statically represented using varargs @return the signature-polymorphic result, statically represented using {@code Object} @throws WrongMethodTypeException if the target's type cannot be adjusted to the caller's symbolic type descriptor @throws ClassCastException if the target's type can be adjusted to the caller, but a reference cast fails @throws Throwable anything thrown by the underlying method propagates unchanged through the method handle call

  public void invoker_call_fallback() throws Throwable {
    DynamicObject object = new DynamicObject();
    MethodHandle fallbackHandle = lookup().findStatic(DynamicObjectTest.class, "fallbackHandle", genericMethodType(2, true));
    object.fallback(fallbackHandle);
    MethodHandle invoker = object.invoker("casper", genericMethodType(3));
    Object result = invoker.invoke(object, "foo", "bar");
    assertThat(result, notNullValue());
    assertThat(result, is((Object) "casper foo bar"));
  }


  @Test

View Full Code Here

  public void invoker_call_fallback_on_setter() throws Throwable {
    DynamicObject object = new DynamicObject();
    MethodHandle fallbackHandle = lookup().findStatic(DynamicObjectTest.class, "fallbackHandle", genericMethodType(2, true));
    object.fallback(fallbackHandle);
    MethodHandle invoker = object.invoker("foo", genericMethodType(2));
    invoker.invoke(object, "bar");
    assertThat(object.get("foo"), is((Object) "bar"));
  }


  @Test
  public void dispatch_calls() throws Throwable {

View Full Code Here

    Object result = env.asFunction("let x = 1\nreturn x + 2");


    assertThat(result, instanceOf(MethodHandle.class));


    MethodHandle func = (MethodHandle) result;
    assertThat((Integer) func.invoke(), is(3));
  }


  @Test
  public void function_with_arguments() throws Throwable {
    EvaluationEnvironment env = new EvaluationEnvironment();

View Full Code Here


    assertThat(result, instanceOf(MethodHandle.class));
    MethodHandle func = (MethodHandle) result;


    assertThat(func.type().parameterCount(), is(2));
    assertThat((Integer) func.invoke(10, 5), is(15));
  }


  @Test
  public void run() throws Throwable {
    EvaluationEnvironment env = new EvaluationEnvironment();

View Full Code Here


    Object result = env.def(code);
    assertThat(result, instanceOf(MethodHandle.class));
    MethodHandle func = (MethodHandle) result;
    assertThat(func.type().parameterCount(), is(2));
    assertThat((Integer) func.invoke(10, 5), is(15));
  }


  @Test
  public void check_source_present_with_compilation_error() {
    EvaluationEnvironment env = new EvaluationEnvironment();

View Full Code Here

  @Test
  @SuppressWarnings("unchecked")
  public void test_asInterfaceInstance() throws Throwable {
    MethodHandles.Lookup lookup = MethodHandles.lookup();
    MethodHandle handle = lookup.findStatic(MyCallable.class, "hello", genericMethodType(0));
    assertThat((String) handle.invoke(), is("Hello!"));
    Callable<Object> converted = (Callable<Object>) Predefined.asInterfaceInstance(Callable.class, handle);
    assertThat((String) converted.call(), is("Hello!"));
  }


  @Test(expectedExceptions = WrongMethodTypeException.class)

View Full Code Here


  @Test(expectedExceptions = WrongMethodTypeException.class)
  public void test_asInterfaceInstance_wrong_target_type() throws Throwable {
    MethodHandles.Lookup lookup = MethodHandles.lookup();
    MethodHandle handle = lookup.findStatic(MyCallable.class, "hello", genericMethodType(0));
    assertThat((String) handle.invoke(), is("Hello!"));
    Predefined.asInterfaceInstance(ActionListener.class, handle);
  }


  @Test
  public void test_fun() throws Throwable {

View Full Code Here

  }


  @Test
  public void test_fun() throws Throwable {
    MethodHandle hello = (MethodHandle) Predefined.fun("hello", MyCallable.class, 0);
    assertThat((String) hello.invoke(), is("Hello!"));
  }


  @Test
  public void test_fun_no_arity() throws Throwable {
    MethodHandle hello = (MethodHandle) Predefined.fun("hello", MyCallable.class);

View Full Code Here

  }


  @Test
  public void test_fun_no_arity() throws Throwable {
    MethodHandle hello = (MethodHandle) Predefined.fun("hello", MyCallable.class);
    assertThat((String) hello.invoke(), is("Hello!"));
  }


  @Test(expectedExceptions = NoSuchMethodException.class)
  public void test_fun_fail() throws Throwable {
    MethodHandle hello = (MethodHandle) Predefined.fun("helloz", MyCallable.class, 0);

View Full Code Here

    }
  }


  private static void callRun(Class<?> klass, String[] arguments) throws Throwable {
    MethodHandle main = publicLookup().findStatic(klass, "main", methodType(void.class, String[].class));
    main.invoke(arguments);
  }


  private static void run(RunCommand golo) throws Throwable {
    try {
      golo.classpath.add(".");

View Full Code Here

0 1 2 3 4 5 6 7 8 9

TOP

All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.