设计模式篇—— 观察者模式

public abstract class AllayControlCenter { 

    public String allayName;   

    public List<Observer> ObsList = new ArrayList<>();

    public String getAllayName() {

        return allayName;

    }

    public void setAllayName(String allayName) {

        this.allayName = allayName;

    }

    public void join(Observer obs) {

        System.out.println(obs.getName() + "加入" + this.getAllayName() +"战队");

        ObsList.add(obs);

    }

    public void quit(Observer obs) {

        System.out.println(obs.getName() + "退出" + this.getAllayName() +"战队");

        ObsList.remove(obs);

    }

    public abstract void notifyObserver(String name) ;

}

public interface Observer {

    public String getName();   

    public void setName(String name);  

    public void beAttacked(AllayControlCenter acc); //收到攻击给指挥中心发送求救信息

    public void help();//接受指挥中心的求救信息   

}

public class Player implements Observer{

    private String name;   

    public Player(String name) {

        this.name = name;

    }

    @Override

    public String getName() {

        return name;

    }  

    @Override

    public void setName(String name) {

        this.name = name;

    }

    @Override

    public void beAttacked(AllayControlCenter acc) {

        System.out.println(this.name + "被攻击，请求支援");

        acc.notifyObserver(name);

    }

    @Override

    public void help() {

        System.out.println("坚持住，" + this.name +"马上到");

    }

}

public class ConcreteAllayControlCenter extends AllayControlCenter {   

    public ConcreteAllayControlCenter(String allyName) {

        System.out.println(allyName + "战队组建成功");

        this.allayName = allyName;

        System.out.println("--------------------------");

    }  

    @Override

    public void notifyObserver(String name) {

        System.out.println(this.getAllayName() + "战队紧急通知，盟友" + name + "收到攻击，请求支援");       

        //遍历队友集合，推送救援消息，去除给自己推送信息

        for(Observer obs : ObsList) {

            if(!obs.getName().equals(name)) {

                obs.help();

            }

        }

    }

}

public class Main {

    public static void main(String[] args) {       

        AllayControlCenter acc = new ConcreteAllayControlCenter("西游大哥");

        Observer ts = new Player("唐僧");

        acc.join(ts);

        Observer wk = new Player("悟空");

        acc.join(wk);

        Observer bj = new Player("八戒");

        acc.join(bj);

        Observer wj = new Player("悟净");

        acc.join(wj);      

        Observer xbl = new Player("小白龙");

        acc.join(xbl); 

        Observer cyj = new Player("程咬金");

        acc.join(cyj);

        acc.quit(cyj);     

        wj.beAttacked(acc);

    }

}