springboot监听器

首先创建类，定义一个事件，继承ApplicationEvent类实现方法

/**
 * 定义一个事件
 */
public class MsgEvent extends ApplicationEvent {
    public MsgEvent(Object source) {
        super(source);
    }
}

定义一个监听者，实现接口ApplicationListener，实现方法，传入MsgEvent这个事件

@Component
public class EmailListener implements ApplicationListener<MsgEvent> {
    @Override
    public void onApplicationEvent(MsgEvent event) {
        String source = (String) event.getSource();
        System.out.println(source + "已经收到您的订单");
    }
}

Controller层实现ApplicationContextAware接口

@RestController
public class UserController implements ApplicationContextAware {


    private ApplicationContext aware;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.aware = applicationContext;
    }

    @GetMapping("/hello")
    public String api(){
        aware.publishEvent(new MsgEvent("下单了"));
        return "下单成功";
    }
}