I know the easy fix for this is to use a interface as a callback in the function parameter, but this library was created from a Kotlin MPP project that targets iOS also. The current api allows lamba calling conventions in Kotlin, iOS and Objective-C. Its only java right now that will have to call it differently. If we changed to use an interface, all languages would have to use a different calling convention....which we would like to avoid. So....besides switching the function signature to use a custom interface, is there another way to call it using Kotlins Function interface?

If you insist on an anonymous class though, it should work too:

doBar(new Function2<>() {
	@Override
	public Unit invoke(String s, Integer[] integers) {
		System.out.println(s);
		System.out.println(integers.length);
		return null;
	}
});