JBoss 4.0.2 EJB3 Problem catching exception while persisting

[jonefun]

I'm using JBoss 4.0.2 with EJB 3.0 support on Firebird 1.5 database.

I intended to place a unique constraint on the Email field of my Customer entity so that I can catch instances where two users attempt to register with the same Email address. My first plan was to do a search before I attempted an insert but then I thought a nicer way would be to put a unique constraint on the Email field of the Customer entity and then catch the Unique constraint exception as part of the normal logic etc.

I have an entity with a field marked as Unique and I insert the same data twice to force a unique constraint exception. The problem is that when I attempt to persist the second entity with the duplicate data the EntityManager does not actually throw an exception ( well it doesn't throw it in my SFSB class anyway )

When I check the JBoss output I can see the exception being caught by the JDBCExceptionReporter, AbstractFlushingEventListener (obviously running as part of the JBoss TransactionManager and on another thread than my SFSB ) and it is being thrown, but it appears that the JBoss implementation of the EntityManager does not actually throw the error and therefore my statefull session bean that is attempting to persist the entity is not aware of the problem.

Obviously the insert fails and the transaction attempts to rollback but I would like to know about the failure in my session bean so that I can take appropriate action.

To summarise :-
1. Create an Entity with a field that has Unique constraint
2. Create a SFSB that has a CreateCustomer method
3. Create a client that calls the SFSB twice with the same data

Problem :-
1. The SFSB does not recieve any kind of Exception as a result of the failed insert
2. JBoss (JDBCExceptionReporter ) catches and logs the JDBC Error
3. The error while captured by the Application Server is never passed to SFSB
4. The Transaction is automatically rolled back even though it is a valid error and continuation is acceptable

If anybody can help me with this I would be very appreciative

Thanks for any help you can give

Cheers

Jonathan

[jonefun]

I've been checking the Hibernate docs for the EntityManager and it suggests that the EntityManager should throw exceptions for errors that occur while interacting with the persistence layer see :-

http://docs.jboss.org/ejb3/HibernateEntityManager/reference/en/html_single/index.html#transactions-demarcation-exceptions

So can anybody comment on why the EntityManager does not throw an exception when I attempt to add two entities with duplicate data in a Field marked as Unique. As I stated earlier the EventListener and AbstractBatchers catch the exception and the JDBCExceptionReporter logs the exception, but that is no use to me when I need to deal with the exception in my StatelessSessionBean.

Any comments ?

[triathlon98]

AFAIU the entitymanager will throw these exceptions. However, it is not stated when these exceptions need to be thrown, and they will (in the case of hibernate) only be throws on session.flush and/or tx commit.

Joachim

[jonefun]

Yes it makes sense for the EntityManager to throw the exception after a flush executes. However it appears that in this situation an exception is not being thrown by the EntityManager.

Question : Is this a bug ? If it is, how do I flag it to the powers that be ?

Jonathan