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JPA-Hibernate - EntityExistsException Question

prasanna kumar

Joined: Jun 27, 2004
Posts: 12
We recently converted our EJB2.1 application to EJB3 (Jboss 4.2.CP07) and landed in to a problem with EntityExistsException Vs DuplicateKeyException (EJB2).
Earlier with EJB2 we were able to do operation like

<EntityHome>.create(<some object>);
} catch (DuplicateKeyException ex) {
Do some other task ..involving database

When we converted to EJB3 ..the code looks like below

em.persist(<some PO>);
} catch (EntityExistsException ex) {
Do some other task ..using em


In second case we learnt that we couldn't do any more operations on the em as the transaction is closed, is this the expected behavior?
If yes can anyone please suggest a different way to handle these scenarios ?

Jeanne Boyarsky
author & internet detective

Joined: May 26, 2003
Posts: 33117

You could call findById first and only persist if it returns null. Exceptions are meant for a non-expected path. It sounds like you are expecting the row might be there.

I have this pattern a lot:
if null: insert record
if not null: merge records

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