WLS10 and Stateless Session Bean

Question

I tried to create EJB3 application example.
1. Created Stateless Session Bean that implements Remote and Local interfaces:
Session Bean code:
package com.session;
import javax.ejb.Local;
import javax.ejb.Remote;
import javax.ejb.Stateless;
import javax.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
@Stateless(mappedName="SessionBeanService")
@Remote(ISessionBeanRemote.class)
@Local(ISessionBeanLocal.class)
@TransactionAttribute(TransactionAttributeType.REQUIRED)
public class SessionBean implements ISessionBeanLocal,
ISessionBeanRemote
public String reply(){
return "MySessionBean - success !!!";
Remote Interface code :
package com.session;
public interface ISessionBeanRemote
public String reply();
Local Interface code:
package com.session;
public interface ISessionBeanLocal
public String reply();
application.xml:
<?xml version="1.0" encoding="UTF-8"?>
<application xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
          http://java.sun.com/xml/ns/javaee/application_5.xsd"
     version="5">
     <display-name>EJB3 Sample Application</display-name>
     <module>
     <ejb>beans.jar</ejb>
     </module>
</application>
weblogic-application.xml:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE weblogic-application PUBLIC
     "-//BEA Systems, Inc.//DTD WebLogic Application 8.1.0//EN"
     "http://www.bea.com/ns/weblogic/90/weblogic-application.xsd">
<weblogic-application>
          <classloader-structure>
               <module-ref>
                    <module-uri>beans.jar</module-uri>
               </module-ref>
          </classloader-structure>
</weblogic-application>
2. I packaged classes into EAR file and deployed to WLS10.
I didn't include any weblogic specific XML descriptors besides weblogic-application.jar.
My client code lookes as follows:
public void test(){
Context context = getMyServerContext();
// THIS JNDI NAME I SEE ON MY SERVER JNDI TREE
String jndiName = "sessionbeansbeans_jarSessionBean_ISessionBeanRemote";
Object obj;
obj = context.lookup(jndiName);
System.out.println(" obj class : " + obj.getClass().getName());
ISessionBeanRemote remote = (ISessionBeanRemote) PortableRemoteObject.narrow(
obj, ISessionBeanRemote.class );
String res = remote.reply();
System.out.println("res : "+res);
I get an Exception:
Exception occurred!
java.lang.ClassCastException: Cannot narrow remote object to com.session.ISessionBeanRemote
     at weblogic.iiop.PortableRemoteObjectDelegateImpl.narrow(PortableRemoteObjectDelegateImpl.java:242)
     at javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:137)
     at ca.cgi.mvest.test.server.wms.GlFacadeTest.runTest(GlFacadeTest.java:91)
     at ca.cgi.mvest.test.server.wms.GlFacadeTest.<init>(GlFacadeTest.java:53)
     at ca.cgi.mvest.test.server.wms.GlFacadeTest.main(GlFacadeTest.java:151)
java.lang.ClassCastException: Cannot narrow remote object to com.session.ISessionBeanRemote
My server console have the following output:
Root cause of ServletException.java.lang.NoClassDefFoundError: com/session/SessionBean_7pp7ls_ISessionBeanRemot
eIntf
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:12
4)
at weblogic.utils.classloaders.GenericClassLoader.defineClass(GenericCla
ssLoader.java:338)
at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(Generic
ClassLoader.java:291)
Truncated. see log file for complete stacktrace
Server logs a problem already on the line when I do lookup
on JNDI name even before narrow();
It looks like my EAR was missing something. But server never complained during deployment.
May be someone can direct me to a real sample of Weblogic10-ejb3.0 application, since examples that come with WLS 10 intallation combersome and do not follow
docmentation.
Thanks in advance for any suggestion.

Answer 1

Hello Freind
The main different b\w stateful and statless is that stateful maintain state of method conversation means it has record that which method call before this method
but in case of stateless conversation state does not saved second different we can say that create method in stateless having no parameter but statefull having parameter I think u can understand easily
With Best Regards
Rajesh Pandey
email :[email protected]
url :-- http://www.sixthquadrant.com
Mob :-- 9811903737
Delhi India