Handling Exceptions

Recovering From a NamingException While Accessing a Remote EJB

If you are trying to remotely access an EJB and you receive an javax.naming.NamingException error, your JNDI properties are probably not initialized properly. See "Load Balancing" for a discussion on setting up JNDI properties when accessing an EJB from a remote object or remote servlet.

Recovering From a NullPointerException While Accessing a Remote EJB

When accessing a remote EJB from a Web application, you receive the following error: "java.lang.NullPointerException: domain was null ". In this case, you must set an environment property in your client while accessing the EJB set dedicated.rmicontext to true.

The following demonstrates how to use this additional environment property:

Hashtable env = new Hashtable( );
env.put (Context.INITIAL_CONTEXT_FACTORY,
  "oracle.j2ee.rmi.RMIInitialContextFactory");
env.put (Context.SECURITY_PRINCIPAL, "oc4jadmin");
env.put (Context.SECURITY_CREDENTIALS, "oc4jadmin");
env.put (Context.PROVIDER_URL, "ormi://myhost-us/ejbsamples");
env.put ("dedicated.rmicontext", "true"); // for 9.0.2.1 and above
Context context = new InitialContext (env);

See "Load Balancing" for more information on dedicated.rmicontext.

Recovering From Deadlock Conditions

If the call sequence of several beans cause a deadlock scenario, OC4J notices the deadlock condition and throws a Remote exception that details the deadlock condition in one of the offending beans.