Bytebuddy: How to generate a native method?

Question

I have an interface

public interface Foo {
    int value();
}

I want to generate an implementation of this interface, where the method is implemented natively:

        final DynamicType.Unloaded<Foo> load = new ByteBuddy()
            .subclass(Foo.class)
            .name("FooNative")
            .initializer(new LoadedTypeInitializer() {
                @Override
                public void onLoad(final Class<?> type) {
                    System.loadLibrary("foo-native");
                }

                @Override
                public boolean isAlive() {
                    return true;
                }
            })
            .method(ElementMatchers.named("foo"))
            .intercept(/* ??? */)
            .make();

How can I generate an empty method with native modifier

@Override public native int value();

?

Answer 1

You would rather use defineMethod and add the native modifier to it. Byte Buddy will automatically detect that it's an override.

Then in the next step, you set withoutCode.