JAVA设计模式-观察者模式

消息发布者找到所有监听者，各个发布事件，实际工作中可用于找到所有实现摸个接口的实现类，统一调用各自的实现方法

public class ObserverTest
{
    public static void main(String[] args) {
        Subject subject = new Subject();
        Listen1 listen1 = new Listen1();
        subject.addObserver(listen1);
        Listen2 listen2 = new Listen2();
        subject.addObserver(listen2);
        subject.publishMsg("消息通知 ");
    }
}

class Subject
{
    // 容器
    private List container = new ArrayList<>();

    // add
    public void addObserver(Listener listener) {
        container.add(listener);
    }

    // remove
    public void remove(Listener listener) {
        container.remove(listener);
    }

    //发布消息
    public void publishMsg(Object object) {
        for (Listener item : container) {
            item.send(object);
        }

    }
}

interface Listener
{
    void send(Object object);
}

class Listen1 implements Listener
{

    @Override
    public void send(Object object) {
        System.out.println(" 观察者1执行: " + object);
    }
}

class Listen2 implements Listener
{

    @Override
    public void send(Object object) {
        System.out.println(" 观察者2执行:" + object);
    }
}