Hello,

We have recently moved our system to JBoss and started to have a mounting avalanche of net.sf.hibernate.NonUniqueObjectException. I cannot track where this is coming from, as it was running perfectly on Tomcat standalone. I tried the system on Weblogic - no problem whatsoever.

Usually the problem appears when there is a one-to-many relation, and I retieve an object via another object. For example,

Uer activeUser = .......... // getting the user
MyProperty myProperty = activeUser.getMyProperty();
..... // some operations
session.saveOrUpdate(activeUser);
// or
session.saveOrUpdate(myProperty);

crashes with net.sf.hibernate.NonUniqueObjectException.

Any idea why this would happen?

Same DB same data ?

Yes, everything is the same.

I tried JBoss 4 and JBoss 3.2.5.

Hibernate connector is implemented through ThreadLocal. I'm changing that, and making the conneciton via JMX. However, IDGenerator does not work in that environment, so we're creating a stateless Session bean wrapper as advised here http://hibernate.org/47.html ... Maybe it'll help, but the error seems very strange.

I have only seen this when you do the following:

open Hibernate session 1
get object with id A from session 1
close session 1
open another session 2
get a new object with id A from session 2
try to save object A from session 1 into session 2


One thing I noticed with using ThreadLocal in JBoss is that JBoss seems to be pooling threads, so when you get a "new" thread, it has pre-existing ThreadLocal variables in it. When I closed my ThreadLocal based session, I made sure that I set the ThreadLocal variable that held the session to null.


Sherman

Setting the thread-local to null is definitely recommended :)