Exceptions

[Sahul Yasin]

Hi All,

Is there any difference in the following scnearios. Pls explain me.

SessionBean calls getPrimaryKey() on its context - IllegalStateException(HFEJB: Page 560)
Client Calls SessionBean getPrimaryKey() on the EJBObject - RemoteException(HFEJB: Page 559)

Thanks & Regards,
Yasin
[ February 25, 2006: Message edited by: Yasin S ]

[Mahesh Subramanian]

As I understood it, Remote client does not get Runtime exceptions from remote EJB object. So it has to get a RemoteException (or subclass) instead of IllegalStateException which is a RuntimeException.

[Balaji Anand]

yes...there are 2 things in exception
bean->container->client
when the bean throws a IllegalStateException or any of the other SystemException the client sees it as either RemoteException or EJBException based on if it is remote or local. The client cant do anything useful with the system exception details.
Page 559 is what the client sees an page 560 is what the bean throws.
Hope this helps

[MI Mohammed]

Ok, if you look at EJBContext interface there is no getPrimaryKey(), so any attempt to call getPrimaryKey() using it's sub interface ie SessionContext object, you can't help it but get a fat java.lang.IllegalStateException.

On the second part, Session beans don't have primary key. but EJBObject interface has a getPrimaryKey(). So, when you call EJBObject.getPrimaryKey() on a session bean, for local client you javax.ejb.EJBException and remote client, java.rmi.RemoteException. Just look at this code

public class MyBean implements SessionBean {
         SessionContext context;
 
      public void setSessionContext(SessionContext context) {
          this.context = context;
      }
 
      // all other call back methods implemented
 
     public void businessMethod() {
       context.getPrimaryKey(); // IllegalStateException
       context.getEJBObject().getPrimaryKey();
      //RemoteException for Remote client
      //EJBException for local Client
    }

I think it's kind of Runtime Exception that is actually thrown from the background.

Whew, hope it helps.

[Sahul Yasin]

Hi All,

Thanks for the replies. I have just taken the exam, scored 88%.

Regards,
Yasin