Pg 556 Exception scenarios answers.

[Arun]

Hello all,
I could not find answers to all the scenarios in page 556, here is a compilation of answers(mine and borrowed from forum). Please post your comments if anything is wrong:

1. A message-drive bean's onMessage() method catches an application exception. Can it rethrow the application exception to the container?
-- No, the onMessage() method does not declare any application exceptions and hence cannot throw the application exception. It can wrap the exception in a runtime exception and rethrow it.

2. A session bean using CMT has a method marked with the NotSupported transaction atrribute While the method is running. the bean calls setRollbackOnly() on its context. will this cause an exception? What kind?
-- Yes, it will cause an exception. It will be an illegalStateException.

3. A message-drive bean, in the onMessage() method, calls getCallerPrincipal(). What happens?
-- Again, an illegalStateException is thrown

4. A session bean using CMT has a method marked with the Madatory transaction attribute. The client calling the method is not in a transaction. What happens?
-- TransactionRequiredException/TransactionRequiredLocalException is thrown.

5. A bean realizes it can't commit a transaction, but it doesn't want the client to get an exception. What can the bean do?
-- Call the setRollBackOnly method and simple suppress the application exception.

6. A bean wants the client to get an application exception, but the bean still wants the transaction to commit. What should the bean do?

-- Simply throw the Application exception as is. It does not have to do anything more.
Regards.

[B.Sathish]

Perfect

[Jonny Andersson]

Thank you for having started this thread! And now about one and a half year later do I try to activate it again from its passivated state because I like it and have a few comments ...

1) Yes, but if the exception is wrapped should it be wrapped as an EJBExcpetion which of course is a RuntimeExcpetion. Alternatively, if the circumstances is appropriate or permits it, could it not just consume the exception?

4) Because they said client would I have answered TransactionRequiredException if I must choose one (on the exam for example) because client if not more exactly specified is a someone that is calling the method remotely.

Maybe someone else have more comments of valuea to add?
[ June 23, 2007: Message edited by: Jonny Andersson ]