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Eclipselink JPA, Oracle, Weblogic, Calling Persist does not commit to database

Answer 1

+1 A:

This might be because you haven't begun a transaction. Try:

public void registerNewUser(String username, String password){
  entityManager.getTransaction().begin();
  User user = new User();
  user.setPassword(password);
  user.setUsername(username);
  entityManager.persist(user);
  entityManager.getTransaction().commit();
}

Although I prefer not to do transaction handling this way. Instead I tend to use Spring's declarative transactions, which would look like this:

@Transactional
public void registerNewUser(String username, String password){
  User user = new User();
  user.setPassword(password);
  user.setUsername(username);
  entityManager.persist(user);
}

when configured.

Edit: Another possibility is a problem I once had with EclipseLink where it wasn't writing everything to the database when I was running it in a J2SE environment (a console app to load some files into a database). In that case I had to explicitly flush() the EntityManager to get all the records written.

cletus 2010-01-05 07:41:03

It's my understanding that you can use container managed transactions in the same way that your 2nd example does this, but using normal java instead of spring. I think this is supposed to be the default (if you don't specify anything), and that you can use the annotation @TransactionManagement(TransactionManagementType.BEAN) to specify manual handling.

MJ 2010-01-05 11:42:21

With your 1st example, I have the following exception:Exception while registering user javax.ejb.EJBException: EJB Exception: : java.lang.IllegalStateException: The method public abstract javax.persistence.EntityTransaction javax.persistence.EntityManager.getTransaction() cannot be invoked in the context of a JTA EntityManager.

MJ 2010-01-05 11:43:01

Answer 2

+1 A:

You can not use the EntityTransaction (em.getTransaction()) because you are using a Container Managed Entity Manager (injected) so you must rely on the container for transactions. Have you set any transactional settings for the Stateless Session bean in XML? If you have not then it should work as the default should be 'Required'. You can try annotating 'registerNewUser' with @TransactionAttribute(TransactionAttributeType.REQUIRED)

Alternatively you could create a user transaction before accessing the EM but a Container Managed transaction would be better.

Gordon Yorke 2010-01-05 14:16:37

Answer 3

A:

After much investigation, including trying both container managed and user managed transactions, it appears that the problem is that the transaction-type is specified as RESOURCE_LOCAL. In this case the following rules apply:

*  You must use the EntityManagerFactory to get an EntityManager
* The resulting EntityManager instance is a PersistenceContext/Cache
* An EntityManagerFactory can be injected via the @PersistenceUnit annotation only (not @PersistenceContext)
* You are not allowed to use @PersistenceContext to refer to a unit of type RESOURCE_LOCAL
* You must use the EntityTransaction API to begin/commit around every call to your EntityManger
* Calling entityManagerFactory.createEntityManager() twice results in two separate EntityManager instances and therefor two separate PersistenceContexts/Caches.
* It is almost never a good idea to have more than one instance of an EntityManager in use (don't create a second one unless you've destroyed the first)

In my case, I needed to use the manager factory to access the entitymanager, and use a persistenceUnit instead of a persistenceContext. The following code works just fine:

@Stateless
@TransactionManagement(TransactionManagementType.CONTAINER)

public class RegisterUser implements RegisterUserLocal {

 @PersistenceUnit(unitName = "SCBCDEntities")
 private EntityManagerFactory factory;

 public void registerNewUser(String username, String password) {

  EntityManager entityManager = factory.createEntityManager();
  EntityTransaction entityTransaction = entityManager.getTransaction();
  entityTransaction.begin();

  User user = new User();
  user.setPassword(password);
  user.setUsername(username);

  entityManager.persist(user);
  entityTransaction.commit();
 }
}

Additional information about configuring transactions and the settings in the persistence.xml can be found here: http://openejb.apache.org/3.0/jpa-concepts.html

MJ 2010-01-06 08:01:57

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