ClassCastException on EJB Remote Lookup/Narrow

[khoff999]

HI - I'm new to JBoss and just trying a simple servlet to remote session bean lookup. I keep getting a ClasscastExcepion on the narrow().

I have a simple EJB - MyBean.class, the remote is My.class, the home is MyHome.class. Here is the servlet lookup code (I try it with and w/o EJB referneces, the result is the same):
__________________________________
InitialContext context = new InitialContext();
Object ref = context.lookup("java:comp/env/ejb/My"); // w/ ref
//Object ref = context.lookup("ejb/My"); // w/o ref
home = (MyHome) PortableRemoteObject.narrow(ref, MyHome.class);
my = home.create();
______________________________________

The lookup returns a object named $Proxy51. The JMX-Console JNDI-view looks like this:

+- ejb (class: org.jnp.interfaces.NamingContext)
| +- My (proxy: $Proxy51 implements interface com.blackdog.interfaces.MyHome,interface javax.ejb.Handle)

There is no other MyHome class in the app that it could be confused with.

This looks like it should work to me. Can anyone suggest what may be going wrong? Thx.

[darranl]

Which version of JBoss are you using?

How is your application actually packaged?

If you have packaged the interfaces in the war file you need to remove them as that is probably the cause of the conflict.

[khoff999]

Thanks for responding. I'm using JBoss 4.0.2.

Yes, the interfaces are in the war file, in a jar under WEB-INF/lib. This was the suggested way to do it in the JBossIDE tutorial. How would you suggest I package them?

[jaikiran]

Place the beans in a jar file, say MyBeans_ejb.jar, and mention this in the application.xml file as follows:


MyBeans_ejb.jar



I think this should work

[darranl]

Have you packaged the jar and war together in an ear?

Just don't add the interfaces jar to the web application. If the beans are deployed within the ear of the war the interfaces will be available at runtime anyway. The section in the tutorial that shows how to do this probably needs to be removed now.

The problem is when they are packaged twice is that they get loaded by two different classloaders which makes them look as if they are different.

[jaikiran]

Sorry, forgot to mention the contents of application.xml in the previous post:

Make an entry as follows:

<module>
 <ejb>MyBeans_ejb.jar</ejb>
 </module>
<module>

And create a jar file MyBeans.jar containing the interfaces and beans

[khoff999]

Yes, everything was in an ear. I did as you suggested and it works fine. Thanks.