设计模式——中介者模式(图)

中介者模式总结如下(可点击放大)：

UML结构图如下：

 

 示例：

public class MediatorTest {
    public static void main(String[] args) {
        Mediator mediator = new ConcreteMediator();
        Colleague c1 = new ConcreteColleague1();
        Colleague c2 = new ConcreteColleague2();

        mediator.register(c1);
        mediator.register(c2);
        c1.send();
        System.out.println("===========");
        c2.send();
    }

}

//中介者接口
interface Mediator {
    void register(Colleague colleague);

    void relay(Colleague colleague);
}

//具体中介者
class ConcreteMediator implements Mediator {
    private List<Colleague> colleagueList = new ArrayList<>();

    @Override
    public void register(Colleague colleague) {
        if (!colleagueList.contains(colleague)){
            colleagueList.add(colleague);
            colleague.setMedium(this);
        }
    }

    @Override
    public void relay(Colleague colleague) {
        for(Colleague c : colleagueList){
            if (!c.equals(colleague)) {
                c.receive();
            }
        }
    }
}

//抽象同事类
abstract class Colleague{
    protected Mediator mediator;

    public void setMedium(Mediator mediator) {
        this.mediator = mediator;
    }

    public abstract void receive();

    public abstract void send();
}

//具体同事类
class ConcreteColleague1 extends Colleague {

    @Override
    public void receive() {
        System.out.println("具体同事类1收到请求");
    }

    @Override
    public void send() {
        System.out.println("具体同事类1发出请求");
        mediator.relay(this);  //请中介者转发
    }
}


//具体同事类
class ConcreteColleague2 extends Colleague {

    @Override
    public void receive() {
        System.out.println("具体同事类2收到请求");
    }

    @Override
    public void send() {
        System.out.println("具体同事类2发出请求");
        mediator.relay(this);  //请中介者转发
    }
}