org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [com.entity.user.User#40288a814a968946014a96896f710008]at org.hibernate.engine.StatefulPersistenceContext.checkUniqueness(StatefulPersistenceContext.java:613)at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.performUpdate(DefaultSaveOrUpdateEventListener.java:307)at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsDetached(DefaultSaveOrUpdateEventListener.java:246)at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.performSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:112)at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)at org.hibernate.impl.SessionImpl.fireSaveOrUpdate(SessionImpl.java:535)at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:527)at org.hibernate.engine.CascadingAction$5.cascade(CascadingAction.java:241)at org.hibernate.engine.Cascade.cascadeToOne(Cascade.java:292)at org.hibernate.engine.Cascade.cascadeAssociation(Cascade.java:240)at org.hibernate.engine.Cascade.cascadePRoperty(Cascade.java:193)at org.hibernate.engine.Cascade.cascade(Cascade.java:154)at org.hibernate.event.def.AbstractSaveEventListener.cascadeBeforeSave(AbstractSaveEventListener.java:454)at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:288)at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:204)at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:144)at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:210)at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:56)at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:195)at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:50)at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:563)at org.hibernate.impl.SessionImpl.save(SessionImpl.java:551)at org.hibernate.impl.SessionImpl.save(SessionImpl.java:547)at com.dao.impl.ReduceHibernateUtil.save2(ReduceHibernateUtil.java:71)at com.dao.impl.Test.main(Test.java:33)