Springboot中的事件Event

事件Event作为一种常用的线程通讯工具，在Springboot中可以方便地提供开发者进行线程交互。

1.事件定义

 1 import org.springframework.context.ApplicationEvent;
 2
 3 /**
 4  * WebSocket触发事件定义
 5  * @author : Asp1rant
 6  * @date : 19-3-11 上午10:33
 7  */
 8
 9 public class WebsocketMessageEvent extends ApplicationEvent {
10
11     public String username;
12     public String message;
13
14     public WebsocketMessageEvent(Object source, String username, String message){
15         super(source);
16         this.username = username;
17         this.message = message;
18     }
19 }

2.编写服务，编写时添加接口供外部调用发布

 1 import com.baosight.tos.util.event.WebsocketMessageEvent;
 2 import org.springframework.beans.factory.annotation.Autowired;
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.stereotype.Service;
 5
 6 /**
 7  * Websocket事件服务
 8  * @author : Asp1rant
 9  * @date : 19-3-11 上午10:36
10  */
11
12 @Service
13 public class WebsocketMessageService {
14
15     @Autowired
16     ApplicationContext applicationContext;
17
18     public void pubWebsocketMessage(String username, String message){
19         applicationContext.publishEvent(new WebsocketMessageEvent(this, username, message));
20     }
21
22 }

3.事件监听，两种写法：

3.1 定义监听器

 1 import org.springframework.context.ApplicationListener;
 2
 3 public class WebsocketEventListener implements ApplicationListener<WebsocketMessageEvent> {
 4
 5     @Override
 6     public void onApplicationEvent(WebsocketMessageEvent websocketMessageEvent){
 7         System.out.println("监听到WebsocketMessageEvent事件");
 8         try {
 9             Thread.sleep(2000);
10         } catch (InterruptedException e) {
11             e.printStackTrace();
12         }
13     }
14
15 }

3.2 注解EventListener

1    @EventListener
2     public synchronized void WebsocketListener(WebsocketMessageEvent event){
3         System.out.println("监听到WebsocketMessageEvent事件");
4     }
5 }