I'm trying to invoke a function, but I 'm getting

java.lang.IllegalArgumentException: Callable expects 4 arguments, but 3 were provided.

This is the place where I'm doing the call:

annotation.listeners.forEach { listener: KClass<*> ->
					listener.functions.forEach { function: KFunction<*> ->
						if (function.name == "before") {
							function.call(annotation.action, request, response)
						}
					}
				}

And this is the method on the interface that's being called:

interface ControllerListener {
	fun before(action: String, request: RestRequest, response: RestResponse)
	fun after(action: String, request: RestRequest, response: RestResponse)
}

What should the fourth paramater be?

an instance of that interface

ah, yes, that makes sense, thanks Ilya!