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JPA Newbie Question

Frank Jones

Joined: Aug 29, 2011
Posts: 8
Hi, I'm trying to set up my first JPA app, and while I'm able to get it to work outside a J2EE container, or within a J2EE container using the following code:

I'm unable to get it to work using the @PersistenceContext annotation. My understanding was that the two below things would both successfully load the EntityManager in the same 'em' reference:



But when I run option 2, I get this error:

I'm sure there's something dumb I'm missing, but if anyone could tell me what it is, I'd be grateful

ps. I am using JBoss 6 and MySQL, if that is relevant.

Frank Jones

Joined: Aug 29, 2011
Posts: 8
Ok I've fixed it, I'll post up what I did in case it saves somebody else the headache I've had trying to get this to work

I think there was two things I did wrong, first I think I was supposed to set 'unitName' on the persistence context, not 'name':

Secondly I packaged the application wrong, I had an ear file, with a WAR, an EJB JAR, a plain JAR and a persistence unit JAR, all in the root. I changed it so that only the WAR and EJB JAR were in the root, and the plain JAR and persistence unit JAR were in the lib subdirectory of the EAR.
I agree. Here's the link:
subject: JPA Newbie Question
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