Can't use RemoteException.getCause() instanceof MyException !!

Question

Hi there, please help me out on this one, I just can't figure out the problem!
I have a swing client and a Session EJB that will throw a DataNotFoundException (subclass of EJBException) if the supplied id was not found in the database:
And as the EJBException is a RuntimeException, it will be autowrapped in RemoteException by the EJB container. Now, on the client we use RemoteException.getCause() to get this DataNotFoundException. getCause returns a Throwable (highest in hierarchy). Now, shouldn't I be able to use instanceof DataNotFoundException?? I mean, it is indeed an exception of this type! But the comparison gives FALSE! However, using (...instanceof Throwable) gives TRUE, as does comparing with Exception!
Anyone knows why I don't get true on (re.getCause() instanceof DataNotFoundException) ??
I'd be very pleased if someone knows the answer!!
Best regards,
AC
(I posted this question on SUN/java language forum too, but got no answers yet!)
try{
filmEJB.insertOrder(orderVO,number);
}catch(RemoteException re){
if (re.getCause() instanceof DataNotFoundException)//returns false!!!
System.out.println("CAUGHT DataNotFoundException");
re.printStackTrace();
//etc, etc

Answer 1

Hi,
Is DataNotFoundException is your own exception class defined!
If so try using the initCause() in your constructor to propagate the exception's cause!
Cheers,
Dwaraka.