detached entity passed to persist

[quilian]

Hello Folks!

in the examples it looks all so easy, but i still dont get it right.

What are the possible reasons for this exception to occur?
javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist

I dont call em.persist nor em.merge or anything. i just want to edit that @DataModelSelection annotated entity in a form and have it persisted.
I saw at least two possible solutions to get the right object:
@DataModelSelection
Entity selectedEntity;

in the booking example HotelBookingAction.java:

 @In(required=false) @Out
 private Hotel hotel;


 @Begin
 public void selectHotel(Hotel selectedHotel)
 {
 hotel = em.merge(selectedHotel);
 }

however both of these option lead to the same error.

So again: what are the reasons for the PersistentObjectException to occur?

Thanks for any hints.
Tobias Kilian

PS: i know this is ejb stuff, so perhaps i should ask there?

[pmuir]

If the entity is detached ;) You need to make sure your persistence context spans the life all the operations you perform with that instance of the entity. Post your code.

[sammy8306]

Right, I always get bitten by these issues too. What problems would I get when using a session-scoped entitymanager? That would solve a lot of issues... (but I'm sure that others would surface..)

[quilian]

The thing was, i used a @PersistenceContext and not the seam managed one.

Thanks for the help anyway.
Tobias

[xshuang]

Hi Guys,

Thanks a lot for this post. It solved my problem also. I am migrating from JBoss to Glassfish then @PersistenceContext EntityManager gave me the same Hibernate error. Change to the @In EntityManager solved the problem.

Thanks,
Sheng