[设计模式]之八:中介者模式

// 比如两个同事分别熟悉CTS和SElinux的问题，现在要找他们协助，就需要找PM协调
// 同事之间不一定都认识，但PM肯定认识。所以PM作为中介者
interface Mediator {
	public void send(String msg, Colleague colleague);
}
// PM认识所有同事，所以会持有同事们的实例，然后管理同事
public class ConcreteMediator implements Mediator {

	private ConcreteColleague1 tom;
	private ConcreteColleague2 jerry;

	public void setTom(ConcreteColleague1 tom) {
		this.tom = tom;
	}

	public void setJerry(ConcreteColleague2 jerry) {
		this.jerry = jerry;
	}
	
	@Override
	public void send(String msg, Colleague colleague) {
		// TODO Auto-generated method stub
		if (colleague.getClass().equals(tom.getClass())) {
			jerry.notify(msg);
		} else {
			tom.notify(msg);
		}
	}

}
//同事只认识PM  由PM转发消息
abstract class Colleague {
	protected Mediator mediator;
	
	public Colleague(Mediator mediator) {
		this.mediator = mediator;
	}
}
public class ConcreteColleague1 extends Colleague {

	public ConcreteColleague1(Mediator mediator) {
		super(mediator);
	}
	
	public void send(String msg) {
		mediator.send(msg, this);
	}
	
	public void notify(String msg) {
		System.out.println("Hi Tom: " + msg);
	}
}
public class ConcreteColleague2 extends Colleague {

	public ConcreteColleague2(Mediator mediator) {
		super(mediator);
	}
	
	public void send(String msg) {
		mediator.send(msg, this);
	}
	
	public void notify(String msg) {
		System.out.println("Hi Jerry: " + msg);
	}

}
//客户代码
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		ConcreteMediator mediator = new ConcreteMediator();
		
		ConcreteColleague1 tom = new ConcreteColleague1(mediator);
		ConcreteColleague2 jerry = new ConcreteColleague2(mediator);
		
		mediator.setTom(tom);
		mediator.setJerry(jerry);
		
		tom.send("Could you do the CTS job?");
		jerry.send("Could you do the SElinux job?");
	}
//输出
Hi Jerry: Could you do the CTS job?
Hi Tom: Could you do the SElinux job?