Spring bean 的创建问题?

Question

先上我的代码

@Component
@Slf4j
public class CSPDJournalListTask {
    @Autowired
    ArticleEntityRepository articleEntityRepository;

    @Async
    public void task2(){
        List<ArticleEntity> list = articleEntityRepository.findAll();
        System.out.println(list.toString());

    }

}

上面是一个异步任务,使用SpringBoot创建,并且已经添加了 @EnableAsync注解

接下来,我就创建了一个简单地单元测试,如下:

@RunWith(SpringRunner.class)
@SpringBootTest
public class CSPDJournalListProcessorTest {


    @Autowired
    CSPDJournalListTask cspdJournalListTask;

    @Test
    public void test() {
        cspdJournalListTask.task();
    }

}

然后,诡异的事情发生了,抛出了如下异常

org.springframework.beans.factory.BeanCreationNotAllowedException: Error creating bean with name 'inMemoryDatabaseShutdownExecutor': Singleton bean creation not allowed while singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:208) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:304) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:515) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.beans.factory.BeanFactoryUtils.beansOfTypeIncludingAncestors(BeanFactoryUtils.java:290) ~[spring-beans-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.detectPersistenceExceptionTranslators(PersistenceExceptionTranslationInterceptor.java:168) ~[spring-tx-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:150) ~[spring-tx-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:135) ~[spring-data-jpa-2.0.8.RELEASE.jar:2.0.8.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61) ~[spring-data-commons-2.0.8.RELEASE.jar:2.0.8.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at com.sun.proxy.$Proxy89.findAll(Unknown Source) ~[na:na]
    at com.example.webmagic_demo.article.CSPDJournalListTask.task2(CSPDJournalListTask.java:43) ~[classes/:na]
    at com.example.webmagic_demo.article.CSPDJournalListTask$$FastClassBySpringCGLIB$$c9b82008.invoke(<generated>) ~[classes/:na]
    at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) ~[spring-core-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:746) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at org.springframework.aop.interceptor.AsyncExecutionInterceptor.lambda$invoke$0(AsyncExecutionInterceptor.java:115) ~[spring-aop-5.0.7.RELEASE.jar:5.0.7.RELEASE]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_171]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[na:1.8.0_171]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[na:1.8.0_171]
    at java.lang.Thread.run(Thread.java:748) ~[na:1.8.0_171]

重点看这句:

Singleton bean creation not allowed while singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!)

好像是说我使用的单实例bean已经关闭了,难道时因为这个异步的原因吗?

如果需要在异步任务中这样做,该怎么实现呢?

希望大神们看到解答一下,非常感谢!

Answer 1

这里贴出我的代码，一点问题也没有

@EnableAsync
@SpringBootApplication
public class Example {

}

@RunWith(SpringRunner.class)
@SpringBootTest(classes = Example.class)
public class Test1 {
    @Autowired
    CSPDJournalListTask cspdJournalListTask;

    @Test
    public void test() {
        cspdJournalListTask.task();
    }
}

@Component
public class CSPDJournalListTask {

        
        @Async
        public void task() {
            // TODO Auto-generated method stub
             System.out.println("async");
        }
        
}

首先要明确的一点是这个错误肯定不是因为使用了async， BeanCreationNotAllowedException大概率是因为项目配置问题，比如jar之间相互冲突不兼容之类的，建议从最简单的项目配置开始，能跑起来之后再增加配置。

Answer 2

@itguang

通常对并发、异步之类的进行单测建议使用 Java 提供的并发工具。

如 CountDownLatch 都可以。

可以参考下文：

深入理解线程间通信