Lookup ejb in another application in same container

Question

Hi,
The 1012 ejb faq http://www.oracle.com/technology/tech/java/oc4j/1012/collateral/OC4J-EJB-FAQ-101202.pdf states:
"If you want to access an EJB in another application in the same OC4J container you do not have to use RMIInitialContextFactory and you can make the application that contains your application as the parent of your application from your you are trying to access EJBs from e.g. ..."
Question: The FAQ implies that the "parent" attribute is NOT necessary to facilitate this situation and RMIInitialContextFactory may be used - is this correct? I have not found any examples that demonstrate how to do this as elsewhere in the Oracle doco they seem to imply that "parent" must be used (but not in 10.1.3). Can anyone please clarify this and/or what works and what doesn't?
Note: The lookup of remote ejb from another application in same container does work without the parent attribute, its just subsequent calls from a 3rd application or redeploy breaks.
My problem: I get a ClassCastException when :
a) lookup remote EJB (in application A) following redeploy of application B
b) the next invocation of the application A method from client application C
Thanks for any advice,
Paul

Answer 1

Your understanding is correct.
If you make application a to be the parent application of app b; then app b could access app a without using RMIInitialContext.
Also you could use RMIInitialContext to obtain the object without using "parent application" approach, example:
Hashtable env = new Hashtable();
env.put("java.naming.factory.initial",
"com.evermind.server.rmi.RMIInitialContextFactory");
env.put("java.naming.provider.url","ormi://remotehost/bmpapp");
env.put("java.naming.security.principal","SCOTT");
env.put("java.naming.security.credentials","TIGER");
Context context = new InitialContext(env);
Object homeObject =
context.lookup("java:comp/env/EmployeeBean");
For this servlet example, you also need to declare <ejb-ref> elements in the web.xml file:
<ejb-ref>
<ejb-ref-name>EmployeeBean</ejb-ref-name>
<ejb-ref-type>Entity</ejb-ref-type>
<home>bmpapp.EmployeeHome</home>
<remote>bmpapp.Employee</remote>
</ejb-ref>
In addition, orion-web.xml, must include a mapping from the logical name EmployeeBean to the actual JNDI name where the EJB is bound, as shown in the following example:
<ejb-ref-mapping name="EmployeeBean" location="bmpapp/EmployeeBean" />
Hope this helps,
-Frances