Spring的事件为Bean与Bean之间的通信提供了支持，当我们系统中某个Spring管理的Bean处理完某件事后，希望让其他Bean收到通知并作出相应的处理，这时可以让其他Bean监听当前这个Bean所发送的事件。
要实现事件的监听，我们要做两件事：
1：自定义事件，继承ApplicationEvent接口
2：定义事件监听器，实现ApplicationListener
3：事件发布类
/**
* @TODO // 自定义事件，继承ApplicationEvent接口
* @Author Lensen
* @Date 2018/7/22
* @Description
*/
public class SendMsgEvent extends ApplicationEvent {
private static final long serialVersionID = 1L;
// 收件人
public String receiver;
// 收件内容
public String content;
public SendMsgEvent(Object source) {
super(source);
}
public SendMsgEvent(Object source, String receiver, String content) {
super(source);
this.receiver = receiver;
this.content = content;
}
public void output(){
System.out.println("I had been sand a msg to " + this.receiver);
}
}
/**
* @TODO //定义事件监听器，实现ApplicationListener
* @Author Lensen
* @Date 2018/7/22
* @Description
*/@Component
public class MsgListener implements ApplicationListener<SendMsgEvent> {
@Override
public void onApplicationEvent(SendMsgEvent sendMsgEvent) {
sendMsgEvent.output();
System.out.println(sendMsgEvent.receiver + "received msg : " + sendMsgEvent.content );
}
}事件发布类
@Component
public class Publisher {
@Autowired
ApplicationContext applicationContext;
public void publish(Object source, String receiver, String content){
applicationContext.publishEvent(new SendMsgEvent(source, receiver, content));
}
}测试消息：WebConfig.class主要是为了扫描Publisher 和Listener类。里面有两个注解@ComponenScan和@Configuration。
public static void main(String[] args) {
AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(WebConfig.class);
Publisher publisher = applicationContext.getBean(Publisher.class);
publisher.publish("Hello,World!","Mr.Lensen", "I Love U");
}结果：
I had been sand a msg to Mr.Lensen
Mr.Lensen received msg : I Love U