CDI @TransactionAttribute for bean
I am experimenting with CDI
on a test application. I have a DAO
which injects a container managed JTA
persistence context like this:
public class TestDAO implements Serializable {
@PersistenceContext
private EntityManager entityManager;
public void insertEntity(Test test) {
entityManager.persist(test);
}
}
Now I have a CDI controller bean like this:
@Named
@SessionScoped
public class TestController implements Serializable {
@Inject
private TestDAO testDAO;
public void finishGame() {
testDAO.insertEntity(new Test(1, 2, 3));
}
}
If I run this, I receive an error in the DAO
when trying to i开发者_运维问答nsert the entity, because there is no active transaction available. So far so good. I can solve this by making the controller bean a stateful EJB
which will wrap the finishGame()
in a transaction.
But let assume I don't want an EJB
. As a test I annotated the finishGame()
with the @TransactionAttribute
annotation and it worked(the controller bean is NOT an EJB
). So my question is: how does it work? Does the CDI
define @TransactionAttribute
for plain beans? I know that Seam Persistence Module
does this, but I am not using it. Actually I added it to the project, but I removed it after, because I received awkward exceptions.
Could anyone clear my confusion? Do really CDI
define @TransactionAttribute
for plain beans?
P.S. I have another sort of question. I see the tendencies is to port all EJB
annotations to plain beans. So will EJBs
become obsolete in the future? I mean I saw in JIRA
that @TransactionAttribute
will be added in the future for plain beans(the task is still not resolved). So isn't this eclipsing EJBs, sort of duplicating functionality?
Best regards, Petar
You need do define a transaction interceptor. Basically define a @Transactional annotation and intercept all methods annotated with it. In the interceptor just begin, commit or rollback the transaction. It gets more complicated when transaction propagation comes into the picture. So check if Seam doesn't have anything ready-to-use http://seamframework.org/Seam3/PersistenceModule
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