ApplicationContext的事件处理——阅读开源项目中的代码

ApplicationContext中的事件处理是通过ApplicationEvent类和ApplicationListener接口来提供的，通过ApplicationContext的publishEvent()方法发布到ApplicationListener; 

组件：被发布的事件，事件发布者，事件监听者

 

流程演示：

　　　1、定义事件，继承ApplicationEvent

　　

import org.springframework.context.ApplicationEvent;

public class DemoEvent extends ApplicationEvent {

    private String msg;
    public DemoEvent(Object source,String msg) {
        super(source);
        this.msg = msg;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }
}

　　2、定义事件监听者，实现ApplicationListener<E>接口

import org.springframework.context.ApplicationListener;
import org.springframework.stereotype.Component;

@Component
public class DemoListener implements ApplicationListener<DemoEvent> {

    @Override
    public void onApplicationEvent(DemoEvent demoEvent) {
        System.out.println("我已经接收到事件："+demoEvent.getMsg());
    }
}

　　3、定义事件推送者：实质是使用ApplicationContext推送事件

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Component;

@Component
public class DemoPublish {

    @Autowired
    private ApplicationContext applicationContext;

    public void publish(String msg){
        applicationContext.publishEvent(new DemoEvent(this,msg));
    }
}

参考博客：https://blog.csdn.net/dongwujing/article/details/89339680