我有一个Spring启动应用程序的问题,它在关闭 @Async
任务(使用EntityManager)之前关闭EntityManager /会话 .
有两个与此问题相关的类:
Scheduler
预定方法保留有限数量的作业,并在 XYJobProcessor
上调用 @Async
方法来执行实际工作 .
@Component
public class XYJobProcessingTimer {
private final XYJobService xyJobService;
private final XYJobProcessor xyJobProcessor;
//constructor skipped
@Scheduled(initialDelayString = "${initial_delay}", fixedDelayString = "${delay}")
public void performXYJobProcessing() {
final String ticket = UUID.randomUUID().toString();
final int reservedJobs = xyJobService.findAndReserveReadyXYJobs(ticket);
if (reservedJobs > 0) {
final Collection<XYJob> xyJobs = xyJobService.readReservedJobs(ticket);
xyJobProcessor.process(xyJobs);
}
}
}
Async Processor
@Async带注释的方法调用访问EntityManager的服务 .
@Service
public class XYJobProcessor {
private final XYJobService xyJobService;
// constructor skipped
@Async("xyJobProcessorExecutor")
public void process(final Collection<XYJob> jobs) {
// This service uses the EntityManager and takes some time depending o job count.
xyJobService.createXYJobsAndDelete(jobs);
}
}
Configuration
运行 @Async
任务的 Executor
的配置 . 创建的Threads是非守护进程 .
@Configuration
public class AsyncExecutorConfiguration {
@Bean(name = "xyJobProcessorExecutor")
public Executor xyJobProcessorExecutor() {
final SimpleAsyncTaskExecutor executor = new SimpleAsyncTaskExecutor();
executor.setConcurrencyLimit(10);
executor.setThreadNamePrefix("Hasselhoff-");
return executor;
}
}
The Problem
当我关闭应用程序时,spring会立即关闭EntityManager会话 - 在所有 @Async
任务完成之前 . 这导致以下异常:
2017-08-31 16:10:54.212 ERROR 12663 --- [Hasselhoff-12] .a.i.SimpleAsyncUncaughtExceptionHandler : Unexpected error occurred invoking async method 'public void de.xy.services.XYJobProcessor.process(java.util.Collection)'.org.springframework.orm.jpa.JpaSystemException: Session is closed!; nested exception is org.hibernate.SessionException: Session is closed!
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:333)
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:244)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:521)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:761)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:730)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:504)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:292)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:673)
at de.xy.services.XYJobService$$EnhancerBySpringCGLIB$$6b9cb1ae.createXYJobsAndDelete(<generated>)
at de.xy.services.XYJobProcessor.process(XYJobProcessor.java:24)
at de.xy.services.XYJobProcessor$$FastClassBySpringCGLIB$$ccc40c8f.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:738)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
at org.springframework.aop.interceptor.AsyncExecutionInterceptor$1.call(AsyncExecutionInterceptor.java:115)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.springframework.core.task.SimpleAsyncTaskExecutor$ConcurrencyThrottlingRunnable.run(SimpleAsyncTaskExecutor.java:268)
at java.lang.Thread.run(Thread.java:748)
Caused by: org.hibernate.SessionException: Session is closed!
at org.hibernate.internal.AbstractSessionImpl.errorIfClosed(AbstractSessionImpl.java:132)
at org.hibernate.internal.SessionImpl.getPersistenceContext(SessionImpl.java:2088)
at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:340)
at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:39)
at org.hibernate.internal.SessionImpl.flush(SessionImpl.java:1282)
at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:465)
at org.hibernate.internal.SessionImpl.flushBeforeTransactionCompletion(SessionImpl.java:2963)
at org.hibernate.internal.SessionImpl.beforeTransactionCompletion(SessionImpl.java:2339)
at org.hibernate.engine.jdbc.internal.JdbcCoordinatorImpl.beforeTransactionCompletion(JdbcCoordinatorImpl.java:485)
at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.beforeCompletionCallback(JdbcResourceLocalTransactionCoordinatorImpl.java:147)
at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.access$100(JdbcResourceLocalTransactionCoordinatorImpl.java:38)
at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl$TransactionDriverControlImpl.commit(JdbcResourceLocalTransactionCoordinatorImpl.java:231)
at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:65)
at org.hibernate.jpa.internal.TransactionImpl.commit(TransactionImpl.java:61)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:517)
... 17 common frames omitted
有没有办法让Spring在关闭EntityManager之前等待 @Async
执行完成?或者这是一个错误?
1 回答
感谢@ M.Deinum,我发现了如何避免这个问题:
使用
ThreadPoolTaskExecutor
(而不是SimpleAsyncTaskExecutor
)并将其awaitTerminationSeconds
属性设置为waitForTasksToCompleteOnShutdown
设置为true
修复了我的问题 .来自
setAwaitTerminationSeconds
的JavaDoc:这是我的问题的确切描述和解决方案 .