设计模式：中间人模式

中间人设计模式是用于协作一组同事。这些同事相互之间不直接沟通，而是通过中介。

在下面的例子中，同事A想要说话，同事B想要打架。当他们做动作（例如doSomething）的时候，他们调用中间人去做那些动作或事情。

1、中间人类图

2、代码实例

package com.leon.mediator;interface IMediator {public void fight();public void talk();public void registerA(ColleagueA a);public void registerB(ColleagueB b);
}//具体的中间人
class ConcreteMediator implements IMediator {ColleagueA a;ColleagueB b;@Overridepublic void fight() {// TODO Auto-generated method stubSystem.out.println("中间人在打架！");}@Overridepublic void talk() {// TODO Auto-generated method stubSystem.out.println("中间人在说话！");}@Overridepublic void registerA(ColleagueA a) {// TODO Auto-generated method stubthis.a = a;}@Overridepublic void registerB(ColleagueB b) {// TODO Auto-generated method stubthis.b = b;}}abstract class Colleague {IMediator mediator;public abstract void doSomething();
}//同事A
class ColleagueA extends Colleague {public ColleagueA(IMediator mediator) {this.mediator = mediator;this.mediator.registerA(this);}@Overridepublic void doSomething() {// TODO Auto-generated method stubthis.mediator.talk();}}//同事B
class ColleagueB extends Colleague {public ColleagueB(IMediator mediator) {this.mediator = mediator;this.mediator.registerB(this);}@Overridepublic void doSomething() {// TODO Auto-generated method stubthis.mediator.fight();}}public class Main {public static void main(String[] args) {IMediator mediator = new ConcreteMediator();ColleagueA talkColleague = new ColleagueA(mediator);ColleagueB fightColleague = new ColleagueB(mediator);talkColleague.doSomething();fightColleague.doSomething();}
}

 
 在其他行为类型的模式中，观察者模式跟中间人模式最为相似。你可以阅读下观察者模式来比较下两者的不同。