//Mediator

abstract class Mediator {

public abstract void notice(String content);

}

//ConcreteMediator

class ConcreteMediator extends Mediator {

private ColleagueA ca;

private ColleagueB cb;

public ConcreteMediator() {

ca = new ColleagueA();

cb = new ColleagueB();

}

public void notice(String content) {

if (content.equals("boss")) {

//老板来了, 通知员工A

ca.action();

}

if (content.equals("client")) {

//客户来了,通知前台B

cb.action();

}

}

}

abstract class Colleague{

public abstract void action();

}

//Colleagueclass

class ColleagueA extends Colleague {

public void action(){

System.out.println("普通员工努力工作");

}

}

class ColleagueB extends Colleague {

public void action() {

System.out.println("前台注意了!");

}

}

public class DS17_Mediator {

public static void main(String[] args) {

Mediator med = new ConcreteMediator();

//老板来了

med.notice("boss");

//客户来了

med.notice("client");

}

}