The afterBegin method notifies a session Bean instance that a new transaction has started, and that
the subsequent business methods on the instance will be invoked in the context of the transaction.
The afterCompletion method notifies a session Bean instance that a transaction commit protocol has
completed, and tells the instance whether the transaction has been committed or rolled back.
An ConnectionSpec holds connection specific properties for use by a
ConnectionFactory in creating a Connection.n Connection in order
to execute a function on the underlying resource.
The EJBException exception is thrown by an enterprise Bean instance to its
container to report that the invoked business method or callback method
could not be completed because of an unexpected error (e.g.