组和规则具有一对多的双向关系。当我在entityManager上调用getSingleResult方法时，我得到了PersistentObjectException：传递给persist的分离实体：Rule
查询是：
entityManager.createQuery("select t from Template t join t.batchContacts bc
join t.groups g where t.enabled = 1 and t.eventType.id=:eventTypeId and
t.media=:media and bc.code =:contactCode and "
+ "g.id =:groupId and t.codes is null");
堆栈跟踪：
org.hibernate.PersistentObjectException: detached entity passed to persist: com.tosan.chapar.core.entity.Rule
at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:127) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.impl.SessionImpl.firePersistOnFlush(SessionImpl.java:834) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.impl.SessionImpl.persistOnFlush(SessionImpl.java:826) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.CascadingAction$9.cascade(CascadingAction.java:357) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascadeToOne(Cascade.java:392) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascadeAssociation(Cascade.java:335) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascadeProperty(Cascade.java:204) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascadeCollectionElements(Cascade.java:425) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascadeCollection(Cascade.java:362) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascadeAssociation(Cascade.java:338) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascadeProperty(Cascade.java:204) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.engine.Cascade.cascade(Cascade.java:161) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.event.def.AbstractFlushingEventListener.cascadeOnFlush(AbstractFlushingEventListener.java:154) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.event.def.AbstractFlushingEventListener.prepareEntityFlushes(AbstractFlushingEventListener.java:145) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:88) ~[hibernate-core-3.6.0.Final.jar:3.6.0.Final]
Wrapped by: javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: com.tosan.chapar.core.entity.Rule
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1214) ~[hibernate-entitymanager-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1147) ~[hibernate-entitymanager-3.6.0.Final.jar:3.6.0.Final]
at org.hibernate.ejb.QueryImpl.getSingleResult(QueryImpl.java:307) ~[hibernate-entitymanager-3.6.0.Final.jar:3.6.0.Final]
at com.tosan.chapar.core.persistence.jpa.TemplateDaoJpa.getTemplate(TemplateDaoJpa.java:262) ~[classes/:na]
at com.tosan.chapar.core.service.impl.TemplateServiceImpl.findEnableGroupAndBatchTemplate(TemplateServiceImpl.java:280) ~[classes/:na]
at com.tosan.chapar.core.service.impl.TemplateServiceImpl$$FastClassBySpringCGLIB$$2a5066e2.invoke(<generated>) ~[classes/:na]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) ~[spring-core-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:720) ~[spring-aop-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) ~[spring-aop-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99) ~[spring-tx-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281) ~[spring-tx-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) ~[spring-tx-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) ~[spring-aop-4.2.9.RELEASE.jar:4.2.9.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.2.9.RELEASE.jar:4.2.9.RELEASE]
我读了类似的问题并尝试调试。但是我仍然无法找到为什么我会得到这个例外以及如何解决它。我需要一些东西来为我揭开神秘面纱，为什么我得到了它，以及如何以最小的副作用解决，因为这些实体在我的项目中使用不同的地方而我没有时间测试所有场景。