如何防止错误 java.lang.IllegalStateException: Transaction already active, in Hibernate答案

【问题标题】：How to prevent the error java.lang.IllegalStateException: Transaction already active, in Hibernate如何防止错误 java.lang.IllegalStateException: Transaction already active, in Hibernate
【发布时间】：2020-03-03 05:01:51
【问题描述】：

我有一个使用 Hibernate 的 Spring Boot 应用程序。以下是我获得 Hibernate 会话的方式：

@Transactional
public class ParentDAO {


        @PersistenceContext
        private EntityManager entityManager;

        protected Session getSession() {

            if(entityManager!=null)
                System.out.println("entity manager instantiated...");

            return entityManager.unwrap(Session.class);
        }



}

然后，我有如下进行数据库访问的类，

@Repository
@Transactional
@SuppressWarnings("unchecked")
public class GmCircularsDaoImpl extends ParentDAO implements IGmCircularsDAO {


    @Override
    public GmCirculars saveOrUpdate(GmCirculars obj) {

        Session session = null;

        try {


            session= this.getSession(); //Added by Zaid

            session.beginTransaction();
            session.saveOrUpdate(obj);
            session.flush();
            session.getTransaction().commit();

        }
        catch (Exception ex) {
            ex.printStackTrace();
        }
        finally {
            session.close();
            System.out.println("Session closed.");
        }
        return obj;
    }


    @Override
    public List<GmCirculars> find(GmCirculars obj, boolean activeOnly, int startOffset, int maxRows) {
        Session session = null;
        List<GmCirculars> discounts = null;

        try {
            if (null != obj) {

                session= this.getSession(); //Added by Zaid

                Criteria criteria = session.createCriteria(GmCirculars.class);

                if (null != obj.getId() && !BigDecimal.ZERO.equals(obj.getId())) {
                    criteria.add(Restrictions.eq("id", obj.getId()));
                }

                if (StringUtil.isNotNullOrEmpty(obj.getTitle())) {
                    criteria.add(Restrictions.ilike("title", obj.getTitle(), MatchMode.ANYWHERE));
                }

                if(null != obj.getOrganizationId()) {
                    criteria.add(Restrictions.eq("organizationId", obj.getOrganizationId()));
                }


                /*if (null != obj.getTypeId() && !BigDecimal.ZERO.equals(obj.getTypeId())) {
                    criteria.add(Restrictions.eq("typeId", obj.getTypeId()));
                }*/


                if (null != obj.getSerialNo() && !BigDecimal.ZERO.equals(obj.getSerialNo())) {
                    criteria.add(Restrictions.eq("serialNo", obj.getSerialNo()));
                }

                if (null != obj.getYear() && !BigDecimal.ZERO.equals(obj.getYear())) {
                    criteria.add(Restrictions.eq("year", obj.getYear()));
                }


                if (activeOnly) {
                    criteria.add(Restrictions.eq("active", BigDecimal.ONE));
                }
                else {
                    criteria.add(Restrictions.or(Restrictions.ne("active", CommonConstants.DELETED_STATUS), Restrictions.isNull("active"))); //Except for deleted ones -> NVL(active,2)
                }


                //LIMIT startOffset, maxRows;
                criteria.setFirstResult(startOffset);
                criteria.setMaxResults(maxRows);

                criteria.addOrder(Order.desc("id"));
                criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);

                System.out.println("criteria: "+ criteria.toString());
                discounts = criteria.list();
                System.out.println("returned list from db:"+discounts);

                //session.getTransaction().commit();

            }

        }
        catch (Exception e) {
            e.printStackTrace();
        }
        finally {
            session.close();
        }
        return discounts;
    }

}

find(GmCirculars obj, boolean activeOnly, int startOffset, int maxRows) 方法首先被调用用于一些查询，它工作得很好。然而，在那之后我打电话给saveOrUpdate(GmCirculars obj)，但我在网上遇到了以下错误：

session.beginTransaction();

错误：

java.lang.IllegalStateException: Transaction already active
    at org.hibernate.engine.transaction.internal.TransactionImpl.begin(TransactionImpl.java:74)
    at org.hibernate.internal.AbstractSharedSessionContract.beginTransaction(AbstractSharedSessionContract.java:467)
    at ae.gov.adm.saeed.dao.impl.circulars.GmCircularsDaoImpl.saveOrUpdate(GmCircularsDaoImpl.java:49)
    at ae.gov.adm.saeed.dao.impl.circulars.GmCircularsDaoImpl$$FastClassBySpringCGLIB$$babc932a.invoke(<generated>)
    at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:769)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:366)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:99)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:747)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:689)
    at ae.gov.adm.saeed.dao.impl.circulars.GmCircularsDaoImpl$$EnhancerBySpringCGLIB$$718dc221.saveOrUpdate(<generated>)
    at ae.gov.adm.saeed.service.circulars.CircularsService.saveOrUpdate(CircularsService.java:37)
    at ae.gov.adm.CircularsMicroservice.saveCircularView(CircularsMicroservice.java:109)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:503)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:590)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:108)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:367)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:860)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1598)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:748)

我试图在重用之前关闭会话

    if(session.isOpen())
        session.close();

每当我再次访问数据库时，我也尝试删除此行，

    session.beginTransaction();

我检查了答案here，但似乎不适用于我的特殊情况。

所有这些尝试都失败了，我不断收到错误。如何解决问题？谢谢。

【问题讨论】：

要么使用@Transactional，要么使用SessionFactory sessionFactory = entityManager.getEntityManagerFactory().unwrap(SessionFactory.class);会话会话 = sessionFactory.openSession();
你为什么使用会话？只需使用EntitiyManager 和persist 即可实现相同的效果。在 JPA 的当前版本/状态下，您通常不希望/不需要使用底层的 Hibernate Session。这只会使您的代码复杂化。话虽如此，不要启动事务也不要提交它（spring 已经这样做了）并且绝对不要关闭会话！这将在 Spring 中破坏正确的处理。

标签： java spring hibernate spring-boot jpa

【解决方案1】：

您的类使用@Transactional 注释，这意味着Spring 已经用事务处理包装了所有方法。如果您查看堆栈跟踪，您可以看到一行

at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:366)

这表明注释正在工作。在离开事务之前，Hibernate 会自动刷新和提交。只需从您的代码中删除事务的手动处理以及 Session.close() 调用，它应该可以工作......

【讨论】：