捕捉休眠异常

Question

我有@Repository如下内容：

@Repository
public class OrderRepository  {

    @Autowired
    SessionFactory sessionFactory;

    public void update(Order order) {

        sessionFactory.getCurrentSession().update(order);
    }
}

由a调用@Service如下：

@Transactional
@Service
public class OrderService {

    @Autowired
    OrderRepository orderRepository;

    public void updateOrder(Order order) {

        orderRepository.update(order);
    }
}

在某些情况下，正在更新的订单已从数据库中删除（这是预期的并且是良性的）。发生这种情况时，将引发异常：

SEVERE: Servlet.service() for servlet [DispatcherServlet] in context with path [/project] threw exception [Request processing failed; nested exception is org.springframework.orm.hibernate4.HibernateOptimisticLockingFailureException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1; nested exception is org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1] with root cause
org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1
    at org.hibernate.jdbc.Expectations$BasicExpectation.checkBatched(Expectations.java:81)
    at org.hibernate.jdbc.Expectations$BasicExpectation.verifyOutcome(Expectations.java:73)
    at org.hibernate.engine.jdbc.batch.internal.NonBatchingBatch.addToBatch(NonBatchingBatch.java:63)
    at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:3281)
    at org.hibernate.persister.entity.AbstractEntityPersister.updateOrInsert(AbstractEntityPersister.java:3183)
    at org.hibernate.persister.entity.AbstractEntityPersister.update(AbstractEntityPersister.java:3525)
    at org.hibernate.action.internal.EntityUpdateAction.execute(EntityUpdateAction.java:159)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:463)
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:349)
    at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:350)
    at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:56)
    at org.hibernate.internal.SessionImpl.flush(SessionImpl.java:1222)
    at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:425)
    at org.hibernate.engine.transaction.internal.jdbc.JdbcTransaction.beforeTransactionCommit(JdbcTransaction.java:101)
    at org.hibernate.engine.transaction.spi.AbstractTransactionImpl.commit(AbstractTransactionImpl.java:177)
    at org.springframework.orm.hibernate4.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:555)
    at org.springframework.transaction.support.AbstractOrderTransactionManager.processCommit(AbstractOrderTransactionManager.java:757)
    at org.springframework.transaction.support.AbstractOrderTransactionManager.commit(AbstractOrderTransactionManager.java:726)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:478)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:272)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:644)
    at uk.co.domain.services.OrderService$$EnhancerBySpringCGLIB$$35a2d392.updateOrder(<generated>)
    at uk.co.domain.controllers.OrderController.test(RequestController.java:51)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)

我试图捕获HibernateOptimisticLockingFailureException存储库中的：

@Repository
public class OrderRepository  {

    @Autowired
    SessionFactory sessionFactory;

    public void update(Order order) {

        try {   
            sessionFactory.getCurrentSession().update(order);
        } catch (HibernateOptimisticLockingFailureException e) {
            System.out.println("Exception occurred");
        }
    }
}

遗憾的是，它不起作用，用户仍然看到异常。我也尝试过捕捉HibernateException，StaleStateException但这些都不起作用。

我尝试将相同的try / catch添加到服务而不是存储库中，但这不起作用。我将不胜感激任何指针。

Answer 1

实际的更新查询在刷新时执行。在会话上调用update（）时不行。在这种特殊情况下，刷新将在包装对服务方法的调用的事务提交之前发生。顺便说一句，可以在堆栈跟踪中看到：

at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:478)

因此，如果要捕获异常，则应在服务之外捕获它：

try {
    orderService.updateOrder(order);
}
catch (ConcurrencyFailureException e) {
    ...
}

即使您从服务或DAO方法中显式地刷新（），捕获异常也是一个坏主意，因为它会使Hibernate会话处于不可靠的状态。应回滚事务，并应立即关闭会话。如果让异常冒泡，那会自动发生，因此最好将其捕获在调用服务的代码中。