Question

我试图通过返回CompletableFuture＆lt;＆gt;来尝试在异步方法中将实体存储在我的数据库中。只要我不检查未来状态（例如isComplete（）或.get（）），代码就可以正常工作。

    CompletableFuture<Product> working = serviceTest.test("working");

以上示例有效，产品存储在数据库中。

    @Async
    public CompletableFuture<Product> test(String name)
    {
       Product p = new Product();
       p.setId(new Random().nextInt(500000));
       p.setName(name);
       logger.info("Saving "+ name);
       p = productRepository.save(p);
       logger.info("finished " + name);
       return CompletableFuture.completedFuture(p);
    }

但是，只要我将代码更改为例如

    CompletableFuture<Product> notWorking = serviceTest.test("notWorking");
    notWorking.get();

实体未保存，代码冻结在＆lt; productRepository.save（p）;＆＃39;。

在异步方法中保存实体的正确方法是什么？请注意，这是一个简化的示例，在实际场景中，测试功能是一个长时间运行的操作，用于从外部服务器获取产品列表。对我来说，无法解释的问题是获得未来状态的简单方法会阻止我的实体的保存。

发生死锁时我提取了一个线程转储。这是相关部分

"MigrationTask-1" #19 prio=5 os_prio=0 tid=0x00007fbdd4bcd800 nid=0x16ea waiting for monitor entry [0x00007fbda9274000]
   java.lang.Thread.State: BLOCKED (on object monitor)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:187)
    - waiting to lock <0x00000000850ab208> (a java.util.concurrent.ConcurrentHashMap)
    at org.springframework.beans.factory.support.AbstractBeanFactory.isTypeMatch(AbstractBeanFactory.java:486)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:432)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:403)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:389)
    at org.springframework.beans.factory.BeanFactoryUtils.beanNamesForTypeIncludingAncestors(BeanFactoryUtils.java:177)
    at org.springframework.beans.factory.annotation.BeanFactoryAnnotationUtils.qualifiedBeanOfType(BeanFactoryAnnotationUtils.java:89)
    at org.springframework.beans.factory.annotation.BeanFactoryAnnotationUtils.qualifiedBeanOfType(BeanFactoryAnnotationUtils.java:66)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.determineQualifiedTransactionManager(TransactionAspectSupport.java:382)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.determineTransactionManager(TransactionAspectSupport.java:363)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:272)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:133)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:57)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
    at com.sun.proxy.$Proxy96.save(Unknown Source)

CompletableFuture.isDone阻止CrudRepository.save（）;

0 个答案: