static {
try {
MethodHandles.Lookup lookup = MethodHandles.lookup();
BIND_CALL_SITE =
lookup.findStatic(
InvokeDynamicSupport.class,
"bindCallSite",
methodType(MethodHandle.class, MethodCallSite.class));
BIND_INIT_CALL_SITE =
lookup.findStatic(
InvokeDynamicSupport.class,
"bindInitCallSite",
methodType(MethodHandle.class, RoboCallSite.class));
MethodHandle cleanStackTrace =
lookup.findStatic(
RobolectricInternals.class,
"cleanStackTrace",
methodType(Throwable.class, Throwable.class));
EXCEPTION_HANDLER =
filterArguments(throwException(void.class, Throwable.class), 0, cleanStackTrace);
GET_SHADOW =
lookup.findVirtual(ShadowedObject.class, "$$robo$getData", methodType(Object.class));
} catch (NoSuchMethodException | IllegalAccessException e) {
throw new AssertionError(e);
}
}
public static void main(String[] args) throws Throwable {
MethodHandles.Lookup lookup = MethodHandles.lookup();
MethodHandle handle = lookup.findStatic(FunctionProgramming.class, "print", typeCallback);
forEach(new Object[] {1, 2, 4}, handle);
MethodHandle handle2 = lookup.findStatic(FunctionProgramming.class, "add", typeCallback2);
Object[] result = map(new Object[] {1, 2, 4}, handle2);
forEach(result, handle);
MethodHandle handle3 = lookup.findStatic(FunctionProgramming.class, "reduce", typeCallback3);
System.out.println(reduce(new Object[] {1, 2, 4}, 0, handle3));
System.out.println(FunctionProgramming.add5(8));
}
public static MethodHandle getMH(Class<?> c) {
try {
return lookup.findStatic(C.class, "m_" + c.getSimpleName(), methodType(c, String.class));
} catch (NoSuchMethodException | IllegalAccessException e) {
throw new RuntimeException(e);
}
}
public static int add5(int a) throws Throwable {
MethodHandles.Lookup lookup = MethodHandles.lookup();
MethodType type = MethodType.methodType(int.class, int.class, int.class);
MethodHandle mhAdd = lookup.findStatic(FunctionProgramming.class, "add", type);
MethodHandle mh = curry(mhAdd, 5);
return (int) mh.invoke(a);
}
static {
try {
MethodHandles.Lookup lookup = MethodHandles.lookup();
THROW_OR_RETURN =
lookup.findStatic(
TestCase.class,
"throwOrReturn",
MethodType.methodType(Object.class, Object.class, Throwable.class));
CATCHER =
lookup.findStatic(
TestCase.class, "catcher", MethodType.methodType(Object.class, Object.class));
FAKE_IDENTITY =
lookup.findVirtual(
TestCase.class, "fakeIdentity", MethodType.methodType(Object.class, Object.class));
} catch (NoSuchMethodException | IllegalAccessException e) {
throw new Error(e);
}
PartialConstructor[] constructors = {
create(Object.class, Object.class::cast),
create(String.class, Objects::toString),
create(int[].class, x -> new int[] {Objects.hashCode(x)}),
create(long.class, x -> Objects.hashCode(x) & (-1L >>> 32)),
create(void.class, TestCase::noop)
};
Throwable[] throwables = {
new ClassCastException("testing"),
new java.io.IOException("testing"),
new LinkageError("testing")
};
List<Supplier<TestCase>> list =
new ArrayList<>(constructors.length * throwables.length * ThrowMode.values().length);
//noinspection unchecked
for (PartialConstructor f : constructors) {
for (ThrowMode mode : ThrowMode.values()) {
for (Throwable t : throwables) {
list.add(f.apply(mode, t));
}
}
}
CONSTRUCTORS = Collections.unmodifiableList(list);
}
static {
final MethodHandles.Lookup lookup = MethodHandles.lookup();
MethodHandle methodHandle = null;
try {
methodHandle = lookup.findStatic(Thread.class, "onSpinWait", methodType(void.class));
} catch (final Exception ignore) {
}
ON_SPIN_WAIT_METHOD_HANDLE = methodHandle;
}
public static void main(String[] args) throws Throwable {
Object x, y;
String s;
int i;
MethodType mt;
MethodHandle mh;
MethodHandles.Lookup lookup = MethodHandles.lookup();
// mt is (char,char)String
mt = MethodType.methodType(String.class, char.class, char.class);
mh = lookup.findVirtual(String.class, "replace", mt);
s = (String) mh.invokeExact("daddy", 'd', 'n');
System.out.println("Result: " + s);
// invokeExact(Ljava/lang/String;CC)Ljava/lang/String;
// weakly typed invocation (using MHs.invoke)
s = (String) mh.invokeWithArguments("sappy", 'p', 'v');
System.out.println("Result: " + s);
// mt is (Object[])List
mt = MethodType.methodType(java.util.List.class, Object[].class);
mh = lookup.findStatic(java.util.Arrays.class, "asList", mt);
assert (mh.isVarargsCollector());
x = mh.invoke("one", "two");
// ArrayList
System.out.println("x: " + x + " type: " + x.getClass().getCanonicalName());
// invoke(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/Object;
// assertEquals(x, java.util.Arrays.asList("one","two"));
// mt is (Object,Object,Object)Object
mt = MethodType.genericMethodType(3);
mh = mh.asType(mt);
x = mh.invokeExact((Object) 1, (Object) 2, (Object) 3);
// invokeExact(Ljava/lang/Object;Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
// 1,2,3
System.out.println("x: " + x + " type: " + x.getClass().getCanonicalName());
// assertEquals(x, java.util.Arrays.asList(1,2,3));
// mt is ()int
mt = MethodType.methodType(int.class);
mh = lookup.findVirtual(java.util.List.class, "size", mt);
i = (int) mh.invokeExact(java.util.Arrays.asList(1, 2, 3));
// invokeExact(Ljava/util/List;)I
assert (i == 3);
mt = MethodType.methodType(void.class, String.class);
mh = lookup.findVirtual(java.io.PrintStream.class, "println", mt);
mh.invokeExact(System.out, "Hello, world.");
// invokeExact(Ljava/io/PrintStream;Ljava/lang/String;)V
}
public static MethodHandle resolveCallHandle() {
try {
return lookup.findStatic(
InterfaceCallSite.class,
"call",
MethodType.methodType(
Object.class, // return type
InterfaceCallSite.class, // interface method being invoked
Object.class, // receiver
Object[].class) // args
);
} catch (Throwable e) {
throw new IllegalStateException(e);
}
}