观察者、代理模式

观察者模式

package designer.one;

import java.util.ArrayList;

public abstract class Observer {
    public ArrayList<Player> players = new ArrayList<>();
    public void add(Player player){
        players.add(player);
    }
    public void remove(Player player){
        players.remove(player);
    }
    public abstract void notifyPlayer();
}

package designer.one;

public class SendObserver extends Observer {
    @Override
    public void notifyPlayer() {
        System.out.println("老师授课结束");
        for (Player player : players) {
            player.response();
        }
    }
}

package designer.one;

public class TeacherObserver extends Observer {
    @Override
    public void notifyPlayer() {
        System.out.println("老师走过来了");
        for (Player player : players) {
            player.response();
        }
    }
}

package designer.one;

public interface Player {
    void response();
}

package designer.one;

public class StudentLol implements Player {
    public String name;

    public StudentLol(String name) {
        this.name = name;
    }

    @Override
    public void response() {
        System.out.println(this.name + "停止了LOL游戏");
    }
}

package designer.one;

public class StudentShengBing implements Player {
    public String name = "";

    public StudentShengBing(String name) {
        this.name = name;
    }

    @Override
    public void response() {
        System.out.println(this.name + "接收视频");
    }
}

package designer.one;

public class TestObserver {
    public static void main(String[] args) {
        StudentLol xiaoming = new StudentLol("小明");
        StudentEnjoy xiaoqing = new StudentEnjoy("小青");

        Observer banzhang = new TeacherObserver();
        banzhang.add(xiaoming);
        banzhang.add(xiaoqing);
        banzhang.notifyPlayer();

        StudentShengBing xiaozhang = new StudentShengBing("小张");
        Observer sendObserver = new SendObserver();
        sendObserver.add(xiaozhang);
        sendObserver.notifyPlayer();
        System.out.println("game over");
    }
}

代理模式

package two;

public class Yingyeting {
    public void sell(){
        System.out.println("卖出去一张票");
    }
}

package two;

public class Proxy {//黄牛
    private Yingyeting yyt;
    public Proxy(){
        this.yyt=new Yingyeting();
    }
    public void sell(){
        System.out.println("吃拿卡要");
        yyt.sell();
    }
}

package two;

public class Consumer {
    Yingyeting yyt = new Yingyeting();
    Proxy huangniu = new Proxy();
    public void ownerBuy(){
        yyt.sell();
    }
    public void buy(){
        huangniu.sell();
    }
}