ApplicationEventPublisher

1、事件类 
@Getter
public class StudentEvent extends ApplicationEvent {
    private Student student;

    public StudentEvent(Object source,Student student) {
        super(source);
        this.student = student;
    }
}


2、ApplicationEventPublisher的publishEvent来发布事件
@Service
public class UserEventRegister {
    @Autowired
    private ApplicationEventPublisher publisher;

    public void register() throws Exception {
        //注册用户
        Student student=new Student();
        student.setId(1);
        student.setName(LocalDateTime.now().toString());

        publisher.publishEvent(new StudentEvent(this,student));

    }
}
3、使用@EventListener来监听事件
@Component
public class UserEventListener {
    @EventListener(value = "StudentEvent.class" ,condition = "#user.name!=null")
    public void handleEvent(StudentEvent studentEvent) throws Exception{
        System.out.println(studentEvent.getName());
        System.out.println(studentEvent.getSex());
    }
}

或

@Service
public class StudentEventService implements ApplicationListener<StudentEvent> {
    @Override
    public void onApplicationEvent(StudentEvent studentEvent) {
        System.out.println("邮件服务接到通知，给 " + studentEvent.getSource() + " 发送邮件...");
    }
}