设计模式-21-中介者模式

中介者模式：用一个中介对象来封装一系列的对象交互

中介者：就像我们在租房子一样，有租房子的中介

代码：


抽象中介者:Mediator

package com.actionPattern.intermediary.edition1;

/*
 * 抽象中介者:Mediator
 */
public abstract class Mediator {
    //申明一个联络方法
    public abstract void constact(String message,Person person);
}

实际中介

package com.actionPattern.intermediary.edition1;

public class MediatorStructure extends Mediator{
    //首先中介结构必须知道所有房主和租房者的信息
    private HouseOwner houseOwner;
    private Tenant tenant;

    public HouseOwner getHouseOwner() {
        return houseOwner;
    }

    public void setHouseOwner(HouseOwner houseOwner) {
        this.houseOwner = houseOwner;
    }

    public Tenant getTenant() {
        return tenant;
    }

    public void setTenant(Tenant tenant) {
        this.tenant = tenant;
    }

    public void constact(String message, Person person) {
        if(person == houseOwner){          //如果是房主，则租房者获得信息
            tenant.getMessage(message);
        }
        else{       //反正则是房主获得信息
            houseOwner.getMessage(message);
        }
    }
}

房主和租房者的抽象

package com.actionPattern.intermediary.edition1;
public abstract class Person {
    protected String name;
    protected Mediator mediator;

    Person(String name,Mediator mediator){
        this.name = name;
        this.mediator = mediator;
    }

}

房主

package com.actionPattern.intermediary.edition1;

/*
 * 房主
 */
public class HouseOwner extends Person{

    HouseOwner(String name, Mediator mediator) {
        super(name, mediator);
    }

    /**
     *  与中介者联系
     * @param message
     * @return void
     */
    public void constact(String message){
        mediator.constact(message, this);
    }

    /**
     *  获取信息
     * @param message
     * @return void
     */
    public void getMessage(String message){
        System.out.println("房主:" + name +",获得信息：" + message);
    }
}

租房者

package com.actionPattern.intermediary.edition1;

/*
 * 租房者
 */
public class Tenant extends Person{

    Tenant(String name, Mediator mediator) {
        super(name, mediator);
    }

    /**
     *  与中介者联系
     * @param message
     * @return void
     */
    public void constact(String message){
        mediator.constact(message, this);
    }

    /**
     *  获取信息
     * @param message
     * @return void
     */
    public void getMessage(String message){
        System.out.println("租房者:" + name +",获得信息：" + message);
    }
}

测试

package com.actionPattern.intermediary.edition1;
public class Client {
    public static void main(String[] args) {
        //一个房主、一个租房者、一个中介机构
        MediatorStructure mediator = new MediatorStructure();

        //房主和租房者只需要知道中介机构即可
        HouseOwner houseOwner = new HouseOwner("张三", mediator);
        Tenant tenant = new Tenant("李四", mediator);

        //中介结构要知道房主和租房者
        mediator.setHouseOwner(houseOwner);
        mediator.setTenant(tenant);

        //房主和租房者都是在向中介者发送消息，中介者更具发送消息者转发消息
        tenant.constact("听说你那里有三室的房主出租.....");
        houseOwner.constact("是的!请问你需要租吗?");
    }
}