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import java.util.ArrayList;public class Observer_Subject { /** * @param args 观察者模式 */ public
static void main(String[] args) { // TODO Auto-generated method stub Cat cat=new
Cat(); Mouse mouse=new
Mouse(cat); People people=new
People(cat); cat.cry(); }}//通知者interface
Subject{ void
AddObserver(Observer obj);}//猫实现了通知者的接口class
Cat implements
Subject{ ArrayList<Observer> arrayList; public
Cat() { arrayList=new
ArrayList<Observer>(); } @Override public
void AddObserver(Observer obj) { // TODO Auto-generated method stub arrayList.add(obj); } void
cry(){//猫叫，通知所有的观察者 for
(Observer obj:arrayList) { obj.responer(); } } }//观察者interface
Observer{ void
responer(); }class
Mouse implements
Observer{ public
Mouse(Cat c) {//将当前的观察者加入到集合中 c.AddObserver(this); } @Override public
void responer() { // TODO Auto-generated method stub System.out.println("老鼠跑"); }}class
People implements
Observer{ public
People(Cat c) { c.AddObserver(this); } @Override public
void responer() { // TODO Auto-generated method stub System.out.println("人醒了"); } } |
原文：http://www.cnblogs.com/daifei/p/3689017.html