package Bean; import Interface.Observer; import Interface.Quackable; /** * Created by Administrator on 2017/7/14. */ public class QuackCounter implements Quackable { Quackable duck; static int numberofQuacks=0; Observable observable; public void registerObserver(Observer observer) { observable.registerObserver(observer); } @Override public void notifyObservers() { observable.notifyObservers(); } public QuackCounter(Quackable duck) { this.duck = duck; observable = new Observable(this); } public void quack() { duck.quack(); numberofQuacks++; notifyObservers(); } public static int getQuacks() { return numberofQuacks; } }