How to use

filterReturn

method

in

com.headius.invokebinder.Binder

  @Override
  public Binder prepareBinder() {
    return Binder
        .from(type())
        .filterReturn(CACHE.bindTo(this));
  }
}

  @Override
  public Binder prepareBinder() {
    return Binder
        .from(type())
        .filterReturn(CACHE.bindTo(this));
  }
}

/**
 * Use the given filter function to transform the return value at this
 * point in the binder. The filter will be inserted into the handle, and
 * return values will pass through it before continuing.
 *
 * The filter's argument must match the expected return value downstream
 * from this point in the binder, and the return value must match the
 * return value at this point in the binder.
 *
 * @param filter the function to use to transform the return value at this point
 * @return a new SmartBinder with the filter applied
 */
public SmartBinder filterReturn(MethodHandle filter) {
  return new SmartBinder(this, signature().changeReturn(filter.type().returnType()), binder.filterReturn(filter));
}

private static MethodHandle createAttrReaderHandle(InvokeSite site, IRubyObject self, RubyClass cls, VariableAccessor accessor) {
  MethodHandle nativeTarget;
  MethodHandle filter = cls.getClassRuntime().getNullToNilHandle();
  MethodHandle getValue;
  if (accessor instanceof FieldVariableAccessor) {
    MethodHandle getter = ((FieldVariableAccessor)accessor).getGetter();
    getValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(Object.class, self.getClass()))
        .invoke(getter);
  } else {
    getValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(Object.class, Object.class))
        .prepend(accessor)
        .invokeVirtualQuiet(LOOKUP, "get");
  }
  // NOTE: Must not cache the fully-bound handle in the method, since it's specific to this class
  return getValue;
}

private static MethodHandle createAttrReaderHandle(InvokeSite site, IRubyObject self, RubyClass cls, VariableAccessor accessor) {
  MethodHandle nativeTarget;
  MethodHandle filter = cls.getClassRuntime().getNullToNilHandle();
  MethodHandle getValue;
  if (accessor instanceof FieldVariableAccessor) {
    MethodHandle getter = ((FieldVariableAccessor)accessor).getGetter();
    getValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(Object.class, self.getClass()))
        .invoke(getter);
  } else {
    getValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(Object.class, Object.class))
        .prepend(accessor)
        .invokeVirtualQuiet(LOOKUP, "get");
  }
  // NOTE: Must not cache the fully-bound handle in the method, since it's specific to this class
  return getValue;
}

private static MethodHandle createAttrWriterHandle(InvokeSite site, IRubyObject self, RubyClass cls, VariableAccessor accessor) {
  MethodHandle nativeTarget;
  MethodHandle filter = Binder
      .from(IRubyObject.class, Object.class)
      .drop(0)
      .constant(cls.getRuntime().getNil());
  MethodHandle setValue;
  if (accessor instanceof FieldVariableAccessor) {
    MethodHandle setter = ((FieldVariableAccessor)accessor).getSetter();
    setValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(void.class, self.getClass(), Object.class))
        .invoke(setter);
  } else {
    setValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(void.class, Object.class, Object.class))
        .prepend(accessor)
        .invokeVirtualQuiet(LOOKUP, "set");
  }
  return setValue;
}

private static MethodHandle createAttrWriterHandle(InvokeSite site, IRubyObject self, RubyClass cls, VariableAccessor accessor) {
  MethodHandle nativeTarget;
  MethodHandle filter = Binder
      .from(IRubyObject.class, Object.class)
      .drop(0)
      .constant(cls.getRuntime().getNil());
  MethodHandle setValue;
  if (accessor instanceof FieldVariableAccessor) {
    MethodHandle setter = ((FieldVariableAccessor)accessor).getSetter();
    setValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(void.class, self.getClass(), Object.class))
        .invoke(setter);
  } else {
    setValue = Binder.from(site.type())
        .drop(0, 2)
        .filterReturn(filter)
        .cast(methodType(void.class, Object.class, Object.class))
        .prepend(accessor)
        .invokeVirtualQuiet(LOOKUP, "set");
  }
  return setValue;
}

/**
 * Use the given filter function to transform the return value at this
 * point in the binder. The filter will be inserted into the handle, and
 * return values will pass through it before continuing.
 *
 * The filter's argument must match the expected return value downstream
 * from this point in the binder, and the return value must match the
 * return value at this point in the binder.
 *
 * @param filter the function to use to transform the return value at this point
 * @return a new SmartBinder with the filter applied
 */
public SmartBinder filterReturn(SmartHandle filter) {
  return new SmartBinder(this, signature().changeReturn(filter.signature().type().returnType()), binder.filterReturn(filter.handle()));
}

.from(site.type())
.permute(2)
.filterReturn(filter);
.from(site.type())
.permute(2)
.filterReturn(filter)
.insert(1, accessor.getIndex())
.cast(Object.class, RubyBasicObject.class, int.class)

.from(site.type())
.permute(2, 3)
.filterReturn(filter);
.from(site.type())
.permute(2, 3)
.filterReturn(filter)
.insert(1, cls.getRealClass(), accessor.getIndex())
.cast(void.class, RubyBasicObject.class, RubyClass.class, int.class, Object.class)

.from(site.type())
.permute(2, 3)
.filterReturn(filter);
.from(site.type())
.permute(2, 3)
.filterReturn(filter)
.insert(1, cls.getRealClass(), accessor.getIndex())
.cast(void.class, RubyBasicObject.class, RubyClass.class, int.class, Object.class)

.from(site.type())
.permute(2)
.filterReturn(filter);
.from(site.type())
.permute(2)
.filterReturn(filter)
.insert(1, accessor.getIndex())
.cast(Object.class, RubyBasicObject.class, int.class)

.permute(2)
.filter(0, receiverConverter)
.filterReturn(filter)
.cast(fieldHandle.type())
.invoke(fieldHandle);
.permute(2, 3)
.filter(0, receiverConverter)
.filterReturn(constant(IRubyObject.class, self.getRuntime().getNil()))
.cast(fieldHandle.type())
.invoke(fieldHandle);

.permute(2)
.filter(0, receiverConverter)
.filterReturn(filter)
.cast(fieldHandle.type())
.invoke(fieldHandle);
.permute(2, 3)
.filter(0, receiverConverter)
.filterReturn(constant(IRubyObject.class, self.getRuntime().getNil()))
.cast(fieldHandle.type())
.invoke(fieldHandle);

if (nativeReturn != void.class) {
  exBinder = exBinder
      .filterReturn(Binder
          .from(newNativeReturn)
          .constant(nullValue(newNativeReturn)));
    .from(site.type())
    .drop(0, isStatic ? 3 : 2)
    .filterReturn(returnFilter)
    .invoke(nativeTarget);

if (nativeReturn != void.class) {
  exBinder = exBinder
      .filterReturn(Binder
          .from(newNativeReturn)
          .constant(nullValue(newNativeReturn)));
    .from(site.type())
    .drop(0, isStatic ? 3 : 2)
    .filterReturn(returnFilter)
    .invoke(nativeTarget);

if (nativeReturn != void.class) {
  exBinder = exBinder
      .filterReturn(Binder
          .from(newNativeReturn)
          .constant(nullValue(newNativeReturn)));
    .from(site.type())
    .drop(0, isStatic ? 3 : 2)
    .filterReturn(returnFilter)
    .invoke(nativeTarget);

if (nativeReturn != void.class) {
  exBinder = exBinder
      .filterReturn(Binder
          .from(newNativeReturn)
          .constant(nullValue(newNativeReturn)));
    .from(site.type())
    .drop(0, isStatic ? 3 : 2)
    .filterReturn(returnFilter)
    .invoke(nativeTarget);

.filterReturn(resultFilter)
.invoke(nativeInvoker);

.filterReturn(resultFilter)
.invoke(nativeInvoker);