Re: EJB, EntityManager and merging problems

Hello,

I've been looking for nice database I/O way and I've decided to use
(suggested by NetBeans) the EJB.

In fact, I was looking for something, which would speed up my work,
unfortunately I'm stuck for last 4 hours with annoying update database
problem.

Fetching data from database works perfectly. BUT, when I'm trying to
update records, I no changes are made in the database. I wish you'll
help me finding the reason.

As it has been described in many, many google-found pages, I've build an
object, which I use as entity manager. Sample:

@Stateless
@TransactionManagement(TransactionManagementType.CONTAINER)
public class UserManager {

    @PersistenceContext(unitName="MyDbPU")
    private EntityManager em;
    @Resource
    SessionContext context;
    @EJB
    private CupUserFacade userFacade; // Dunno whether it's required?

    public int UpdateUser() {
        EntityManagerFactory emf =
        Persistence.createEntityManagerFactory("MyDbPU");

        em = emf.createEntityManager();
        CupUser user = (CupUser) em.find(CupUser.class, 2);
    user.setName("fonk you");
        try {
            CupUser upUser = em.merge(user);
            System.err.println(upUser.getName());
            em.close();

            return 1;
        } catch (Exception ex) {
            System.err.println(
        "UserManager.UpdateUser(): "
            + ex.getMessage());
            return 0;

        }
    }

    @PersistenceContext
    public void setEntityManager(EntityManager eman) {
        this.em = eman;
    }
}

The log file sayz:

FINEST: Execute query ReadObjectQuery(referenceClass=CupUser sql="SELECT
... FROM cup_user WHERE (ID = ?)")
SEVERE: fonk you
FINEST: Merge clone with references entity.CupUser[id=2]
SEVERE: true // is open() EntityManager
FINER: release unit of work

In fact it does not say anything about updating queries...
That's annoying, because I really don't know what am I doing wrong.

Please help. Thank you very much.

Przemek M. Zawada