Spring中事件机制的实现示例

public class MyEvent extends ApplicationEvent {
    
    public MyEvent(Object source) {
        super(source);
    }
}

@Autowired
    private ApplicationEventPublisher applicationEventPublisher;
    public void enent(){
        //业务代码
        //发送事件
        applicationEventPublisher.publishEvent(new MyEvent(this));
    }

@Component
public class MyLin implements ApplicationListener<MyEvent> {
    @Override
    public void onApplicationEvent(MyEvent event) {
        System.out.println("监听到事件");
    }
}

@Component
public class MyLin2 {
    //注意方法的参数类型是监听的类型
    @EventListener
    public void onApplicationEvent(MyEvent event) {
        System.out.println("监听到事件2");
    }
}

    @Bean
    public SimpleApplicationEventMulticaster applicationEventMulticaster(ThreadPoolExecutor executor){
        SimpleApplicationEventMulticaster multicaster = new SimpleApplicationEventMulticaster();
        multicaster.setTaskExecutor(executor);
        return multicaster;
    }

@Component
public class AsyncEventListener {
    
    private static final Logger logger = LoggerFactory.getLogger(AsyncEventListener.class);
    
    /**
     * 异步处理事件 - 不会阻塞主线程
     */
    @Async("taskExecutor")  // 指定使用配置的线程池
    @EventListener
    public void handleAsyncEvent(MyEvent event) {
        logger.info("异步事件处理开始 - 事件: {}", event.getMessage());
        logger.info("当前线程: {}", Thread.currentThread().getName());
        
        try {
            // 模拟耗时操作
            Thread.sleep(3000);
            logger.info("异步事件处理完成: {}", event.getMessage());
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
            logger.error("异步事件处理被中断", e);
        }
    }
    
    /**
     * 同步处理事件 - 会阻塞主线程
     */
    @EventListener
    public void handleSyncEvent(MyEvent event) {
        logger.info("同步事件处理开始 - 事件: {}", event.getMessage());
        logger.info("当前线程: {}", Thread.currentThread().getName());
        
        try {
            // 模拟耗时操作
            Thread.sleep(2000);
            logger.info("同步事件处理完成: {}", event.getMessage());
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
            logger.error("同步事件处理被中断", e);
        }
    }
}

@SpringBootTest
public class EventTest {
    
    @Autowired
    private BusinessService businessService;
    
    @Test
    public void testAsyncEvent() {
        System.out.println("测试开始 - 主线程: " + Thread.currentThread().getName());
        
        long startTime = System.currentTimeMillis();
        businessService.doBusiness();
        long endTime = System.currentTimeMillis();
        
        System.out.println("业务方法执行时间: " + (endTime - startTime) + "ms");
        
        // 给异步事件处理留出时间
        try {
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    }
}