Jagepard / JavaDesignPatterns-Mediator

public class Main {

    public static void main(String[] args) throws Exception {

        HandlerInterface handler   = new Handler();

        MediatorInterface mediator = new Mediator();

        AbstractListener listener1 = new Colleague1();

        AbstractListener listener2 = new Colleague2();

        AbstractListener listener3 = new Colleague3();

        try {

            mediator.addListener(listener1, "onEvent");

            mediator.addListener(listener2, "onEvent");

            mediator.addListener(listener3, "onEvent");

            handShake(handler, mediator, listener1, listener2);

            handShake(handler, mediator, listener2, listener3);

            handShake(handler, mediator, listener3, listener1);

        } catch (Exception e) {

            System.out.printf("Caught exception: %s \n", e.getLocalizedMessage());

        }

    }

    private static void handShake(HandlerInterface handler, MediatorInterface mediator, AbstractListener listener1, AbstractListener listener2) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {

        ArrayList<String> result1 = listener1.toGreet(listener2.getClass().getName(), mediator, handler);

        System.out.println(result1.get(0));

        System.out.println(result1.get(1));