我正在使用带有 @EnableScheduling 和 @EnableAsync 的 Spring boot。

我有一个用@Scheduled 注释的方法。 我还有一些方法，用 @Async 注释。

现在我在 @Scheduled 方法中调用这些 @Async 方法，并在异步方法中打印出当前线程的名称。我看到的是它们都有相同的线程名称，实际上是运行 @Scheduled 方法的线程。

我没有看到异步方法执行。 这里有什么问题？

这是我的应用程序启动类

@SpringBootApplication
@EnableScheduling
@EnableAsync
public class ApplicationBoot {

    public static void main(String[] args) {
        SpringApplication.run(ApplicationBoot.class, args);
    }
}

这是我的调度类

@Component
public class TaskScheduler {
    private static final Logger logger = Logger.getLogger(TaskScheduler.class);

    @Scheduled(fixedDelay = 10000)
    public void ScheduledMethod() {
        methodOne();
        methodTwo();
        methodThree();
    }

    @Async
    private void methodOne() {
        logger.info("Method one called  by Thread : " + Thread.currentThread().getName() + "  at " + new Date());
    }

    @Async
    private void methodTwo() {
        logger.info("Method two called  by Thread : " + Thread.currentThread().getName() + "  at " + new Date());
    }

    @Async
    private void methodThree() {
        logger.info("Method three called  by Thread : " + Thread.currentThread().getName() + "  at " + new Date());
    }
}

输出

Thread 调用的方法一:pool-1-thread-1 at Tue Apr 04 16:32:27 IST 2017

Thread 调用的方法二:pool-1-thread-1 at Tue Apr 04 16:32:27 IST 2017

Thread 调用的方法三:pool-1-thread-1 at Tue Apr 04 16:32:27 IST 2017

最佳答案

解释

Spring 围绕您的实例创建一个代理。 ScheduledMethod 在内部调用 3 个方法，这些方法没有代理，因此不是异步的。

cf. the documentation :

If you invoke a method on an object reference, the method is invoked directly on that object reference, as can be seen below.

看这个问题Spring AOP not working, when the method is called internally within a bean 一种变通方法，但最好的方法是文档中提出的 最好的方法(术语 best 在这里松散地使用)是重构你的代码，这样就不会发生自调用......

请注意，私有(private)方法不是 supported too :

Due to the proxy-based nature of Spring’s AOP framework, protected methods are by definition not intercepted, neither for JDK proxies (where this isn’t applicable) nor for CGLIB proxies (where this is technically possible but not recommendable for AOP purposes). As a consequence, any given pointcut will be matched against public methods only!

解决方法示例

@Component
public class ServiceMethod {
    private static final Logger logger = Logger.getLogger(ServiceMethod .class);

    @Async
    public void methodOne() {
        logger.info("Method one called  by Thread : " + Thread.currentThread().getName() + "  at " + new Date());
    }

    @Async
    public void methodTwo() {
        logger.info("Method two called  by Thread : " + Thread.currentThread().getName() + "  at " + new Date());
    }

    @Async
    public void methodThree() {
        logger.info("Method three called  by Thread : " + Thread.currentThread().getName() + "  at " + new Date());
    }
}

@Component
public class TaskScheduler {
    private static final Logger logger = Logger.getLogger(TaskScheduler.class);

    @Autowired
    private ServiceMethod serviceMethod;

    @Scheduled(fixedDelay = 10000)
    public void ScheduledMethod() {
        serviceMethod.methodOne();
        serviceMethod.methodTwo();
        serviceMethod.methodThree();
    }
}

关于java - @Scheduled 方法中的 Spring @Async 方法调用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/43204817/