We are working on Hibernate upgrade in my project. We were on hibernate 3.3.1, spring version 3.1.1 and working with JPA 2.0 as persistence layer. Now I am trying to upgrade Hibernate 4.3.1. we have done all necessary dependencies for this upgrade.

Able to build our project fine but when I run our JUnit tests, am getting Found shared references to a collection error (I have upgraded to Hibernate 4.3.1 with JPA 2.1 and Spring 3.1.1 in our project now). Can you please help me to solve this error .

Caused by: org.hibernate.HibernateException: Found shared references to a collection: com.carlson.cwt.portrait.domain.traveler.BusinessT raveler.addresses
at org.hibernate.engine.internal.Collections.processR eachableCollection(Collections.java:180)
at org.hibernate.event.internal.FlushVisitor.processC ollection(FlushVisitor.java:59)
at org.hibernate.event.internal.AbstractVisitor.proce ssValue(AbstractVisitor.java:121)
at org.hibernate.event.internal.AbstractVisitor.proce ssValue(AbstractVisitor.java:82)
at org.hibernate.event.internal.AbstractVisitor.proce ssEntityPropertyValues(AbstractVisitor.java:76)
at org.hibernate.event.internal.DefaultFlushEntityEve ntListener.onFlushEntity(DefaultFlushEntityEventLi stener.java:172)
at com.carlson.cwt.portrait.domain.event.ProfileEntit yFlushEventListener.onFlushEntity(ProfileEntityFlu shEventListener.java:37)
at org.hibernate.event.internal.AbstractFlushingEvent Listener.flushEntities(AbstractFlushingEventListen er.java:231)
at org.hibernate.event.internal.AbstractFlushingEvent Listener.flushEverythingToExecutions(AbstractFlush ingEventListener.java:102)
at org.hibernate.event.internal.DefaultAutoFlushEvent Listener.onAutoFlush(DefaultAutoFlushEventListener .java:61)
at org.hibernate.internal.SessionImpl.autoFlushIfRequ ired(SessionImpl.java:1187)
at org.hibernate.internal.SessionImpl.list(SessionImp l.java:1253)
at org.hibernate.internal.QueryImpl.list(QueryImpl.ja va:103)
at org.hibernate.jpa.internal.QueryImpl.list(QueryImp l.java:573)
at org.hibernate.jpa.internal.QueryImpl.getResultList (QueryImpl.java:449)
at org.springframework.orm.jpa.JpaTemplate$12.doInJpa (JpaTemplate.java:370)
at org.springframework.orm.jpa.JpaTemplate$12.doInJpa (JpaTemplate.java:1)
at org.springframework.orm.jpa.JpaTemplate.execute(Jp aTemplate.java:187)
... 42 more

My mappings are as below between BusinessTraveler and TravelerAddress:

in BusinessTraveler class:
@OneToMany (cascade = CascadeType.ALL, orphanRemoval = true, mappedBy = "businessTraveler")
private Set<TravelerAddress> addresses = new HashSet<TravelerAddress>();

in TravelerAddress class:
@ManyToOne
@JoinColumns ({
@JoinColumn (name = "BUSINESS_TRAVELER_ID", nullable = false, insertable = false, updatable = false),
@JoinColumn (name = "BUSINESS_TRAVELER_ORIG_ID", nullable = false, insertable = false, updatable = false) })
private BusinessTraveler businessTraveler;

Is this Found shared references to a collection occurs due to mappings? or because of some else in project??

Hi, did you ever determine what the problem was here?
We have same issue after hib upgrade

One way this can happen is when your code has somehow tried to share the same collection object reference between two different entities instances.

eg:
masterTwo.setSlaves( masterOne.getSlaves() );

In your case, it would imply using the same Set object from one BusinessTraveller instance in another BusinessTraveller instance.

However, that would throw the exception at commit time, and looking at your stack trace it appears to be occuring when hibernate is reconstituting the objects to return to you as query results.

This suggests that maybe the old data you are running the unit tests against contains values for your composite foreign key which are 'bad'?

Unfortunately I'm not really familiar enough with the JPA annotions to make good suggestions about what exactly to look for in that case.

I did notice docs for @JoinColumns which state: "When the JoinColumns annotation is used, both the name and the referencedColumnName elements must be specified in each such JoinColumn annotation. ".

You aren't specifying the referencedColumn in the annotations, I think implying both FK columns in your composite FK would refer to the PK of BusinessTraveller? - which doesn't quite make sense since only one BusinessTraveller can own a particular TravellerAdress entity as it is a One BusinessTraveller to Many TravellerAddress relationship and if they refer to different BusinessTravellers... that wouldnt make sense for a OneToMany/ManyToOne.