Problem of EJB module deploy & access

[Mike Sever]

IBM WEBSPHERE APPLICATION SERVER, v. 6.0.2
1. install application[1]: one ear file includes one ejb module and web module[1]
2. install application[2]: one web module[2]
I can access ejb module by web module[1], but can NOT by web module[2], (see below exception when narrowing TestEJBHome). Is it due to they locating in different applications???
If true, I can not share the ejb module in two web modules, can I? That means I should bind web module with it as one application once I want to access ejb module.
Then can I access ejb module from a different machine (by modifying the ip of url when creating InitialContext)?

The below is the detailed infomation, jsp file and web.xml are same in web module[1] and web module[2], and the two class files TestEJB & TestEJBHome are archived as a jar file located in web module's lib folder.

---web module---
jsp file:

String url = "iiop://localhost:2809";
Properties properties = new Properties();
properties.put(Context.INITIAL_CONTEXT_FACTORY, "com.ibm.websphere.naming.WsnInitialContextFactory");
properties.put(Context.PROVIDER_URL, url);
 
Context initCtx = new InitialContext(properties);
Object ref = initCtx.lookup("java:comp/env/ejb/TestEJB");
TestEJBHome testEJBHome= (TestEJBHome) PortableRemoteObject.narrow(ref, TestEJBHome.class);

web.xml:

<ejb-ref>
<ejb-ref-name>ejb/TestEJB</ejb-ref-name>
<ejb-ref-type>Session</ejb-ref-type>
<home>com.test.TestEJBHome</home>
<remote>com.test.TestEJB</remote>
<ejb-link>test_ejb.jar#TestEJB</ejb-link>
</ejb-ref>

---ejb module---
ejb-jar.xml:

<ejb-jar>
<display-name>test_ejb</display-name>
<enterprise-beans>
    <session>
      <display-name>TestEJB</display-name>
      <ejb-name>TestEJB</ejb-name>
      <home>com.test.TestEJBHome</home>
      <remote>com.test.TestEJB</remote>
      <local-home>com.test.TestEJBLocalHome</local-home>
      <local>com.test.TestEJBLocal</local>
      <ejb-class>com.test.TestEJBBean</ejb-class>
      <session-type>Stateless</session-type>
      <transaction-type>Container</transaction-type>
    </session>
  </enterprise-beans>  
  <assembly-descriptor>
    <container-transaction>
      <method>
        <ejb-name>TestEJB</ejb-name>
        <method-name>*</method-name>
      </method>
      <trans-attribute>Required</trans-attribute>
    </container-transaction>        
  </assembly-descriptor>  
</ejb-jar>

Error log:

[7/25/06 10:28:23:982 CST] 00000039 SystemErr     R java.lang.ClassCastException: Unable to load class: com.test._TestEJBHome_Stub
at com.ibm.rmi.javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:366)
at javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:157)
at com.ibm._jsp._test._jspService(_test.java:92)
at com.ibm.ws.jsp.runtime.HttpJspBase.service(HttpJspBase.java:88)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1282)
at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:673)
at com.ibm.wsspi.webcontainer.servlet.GenericServletWrapper.handleRequest(GenericServletWrapper.java:117)
at com.ibm.ws.jsp.webcontainerext.JSPExtensionServletWrapper.handleRequest(JSPExtensionServletWrapper.java:178)
at com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest(CacheServletWrapper.java:89)
at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:1896)
at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:84)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:472)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation(HttpInboundLink.java:411)
at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.ready(HttpInboundLink.java:288)
at com.ibm.ws.tcp.channel.impl.NewConnectionInitialReadCallback.sendToDiscriminaters(NewConnectionInitialReadCallback.java:201)
at com.ibm.ws.tcp.channel.impl.NewConnectionInitialReadCallback.complete(NewConnectionInitialReadCallback.java:103)
at com.ibm.ws.tcp.channel.impl.WorkQueueManager.requestComplete(WorkQueueManager.java(Compiled Code))
at com.ibm.ws.tcp.channel.impl.WorkQueueManager.attemptIO(WorkQueueManager.java(Compiled Code))
at com.ibm.ws.tcp.channel.impl.WorkQueueManager.workerRun(WorkQueueManager.java(Compiled Code))
at com.ibm.ws.tcp.channel.impl.WorkQueueManager$Worker.run(WorkQueueManager.java(Compiled Code))
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1462)
 
[7/25/06 10:28:23:982 CST] 00000039 SystemErr     R at com.ibm.rmi.javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:366)
[7/25/06 10:28:23:982 CST] 00000039 SystemErr     R at javax.rmi.PortableRemoteObject.narrow(PortableRemoteObject.java:157)
[7/25/06 10:28:23:982 CST] 00000039 SystemErr     R at com.ibm._jsp._test._jspService(_test.java:92)
[7/25/06 10:28:23:985 CST] 00000039 SystemErr     R at com.ibm.ws.jsp.runtime.HttpJspBase.service(HttpJspBase.java:88)
[7/25/06 10:28:23:985 CST] 00000039 SystemErr     R at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
[7/25/06 10:28:23:986 CST] 00000039 SystemErr     R at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1282)
[7/25/06 10:28:23:986 CST] 00000039 SystemErr     R at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:673)
[7/25/06 10:28:23:986 CST] 00000039 SystemErr     R at com.ibm.wsspi.webcontainer.servlet.GenericServletWrapper.handleRequest(GenericServletWrapper.java:117)
[7/25/06 10:28:23:986 CST] 00000039 SystemErr     R at com.ibm.ws.jsp.webcontainerext.JSPExtensionServletWrapper.handleRequest(JSPExtensionServletWrapper.java:178)
[7/25/06 10:28:23:986 CST] 00000039 SystemErr     R at com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest(CacheServletWrapper.java:89)
[7/25/06 10:28:23:986 CST] 00000039 SystemErr     R at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:1896)
[7/25/06 10:28:23:986 CST] 00000039 SystemErr     R at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:84)
[7/25/06 10:28:23:987 CST] 00000039 SystemErr     R at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:472)
[7/25/06 10:28:23:987 CST] 00000039 SystemErr     R at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation(HttpInboundLink.java:411)
[7/25/06 10:28:23:987 CST] 00000039 SystemErr     R at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.ready(HttpInboundLink.java:288)
[7/25/06 10:28:23:987 CST] 00000039 SystemErr     R at com.ibm.ws.tcp.channel.impl.NewConnectionInitialReadCallback.sendToDiscriminaters(NewConnectionInitialReadCallback.java:201)
[7/25/06 10:28:23:987 CST] 00000039 SystemErr     R at com.ibm.ws.tcp.channel.impl.NewConnectionInitialReadCallback.complete(NewConnectionInitialReadCallback.java:103)
[7/25/06 10:28:23:987 CST] 00000039 SystemErr     R at com.ibm.ws.tcp.channel.impl.WorkQueueManager.requestComplete(WorkQueueManager.java(Compiled Code))
[7/25/06 10:28:23:987 CST] 00000039 SystemErr     R at com.ibm.ws.tcp.channel.impl.WorkQueueManager.attemptIO(WorkQueueManager.java(Compiled Code))
[7/25/06 10:28:23:988 CST] 00000039 SystemErr     R at com.ibm.ws.tcp.channel.impl.WorkQueueManager.workerRun(WorkQueueManager.java(Compiled Code))
[7/25/06 10:28:23:988 CST] 00000039 SystemErr     R at com.ibm.ws.tcp.channel.impl.WorkQueueManager$Worker.run(WorkQueueManager.java(Compiled Code))
[7/25/06 10:28:23:988 CST] 00000039 SystemErr     R at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1462)

Anyone who knows it helps me please, thanks a lot! (Waiting in sweat...)

[Jaikiran Pai]

Object ref = initCtx.lookup("java:comp/env/ejb/TestEJB");

You are looking up a local home object and *not* a remote one. So your code should look like:

String url = "iiop://localhost:2809";
Properties properties = new Properties();
properties.put(Context.INITIAL_CONTEXT_FACTORY, "com.ibm.websphere.naming.WsnInitialContextFactory");
properties.put(Context.PROVIDER_URL, url); 
 
Context initCtx = new InitialContext(properties);
Object ref = initCtx.lookup("java:comp/env/ejb/TestEJB");
 
[B]TestEJBLocalHome testEJBLocalHome= (TestEJBLocalHome) ref;[/B]

[Mike Sever]

Thanks for reply, but ...
1. Pls note: code in jsp file can run well in web module[1] which locates in the same application with ejb module, but exception occurs when called from web mdoule[2];
2. After using "TestEJBLocalHome testEJBLocalHome= (TestEJBLocalHome) ref;" in web module[1], it threw "Unable to load class: com.citigroup.apac.cpbol.middleware.test._TestEJBHome_Stub".

The configuration of calling remote object (web.xml, ejb-jar.xml) seems available and calling from web module within the same application works, but if that web module is not in the same application with ejb module, it seems NOT ...

I am not familiar with websphere at all. Previously in weblogic 8.1, I can just do below:
1. ear (including ejb module) under "Deployments\Applications"
2. web module[1], web module[2] under "Deployments\Web Application Modules"
And since global JNDI name can be access, ejb-jar.xml & weblogic-ejb-jar.xml are enough. Then, calling ejb from web module[1] and web module[2] are both ok.

[Jaikiran Pai]

[7/25/06 10:28:23:982 CST] 00000039 SystemErr R java.lang.ClassCastException

Looks like the classloader issue. Do you have the remote/local interface classes in 2 different jars? I guess, yes(one in jar files of webmodule[2] and one in jar files on ejb module[1]). If that's the case, do you have classloader isolation of the 2 applications. I *guess*, since the remote/local interface classes are being loaded by two different classloaders, you are seeing the ClassCastException. Just as a *temporary* test, remove the remote/local interfaces from one of the jars(ideally, webmodule[2]) and try out.

I am not aware about how Classloading isolation is achieved in Websphere, so am not able to pinpoint as to what exactly might be the issue.

[Mike Sever]

scenario:
1. app1: ejb module, web module
2. app1: ejb module, web module[1]
app2: web module[2]
3. app1: ejb module
app2: web module[2]
I've reviewed the configuration of weblogic. All web module and ejb module are in the same application instance...
Then, in scenario 2 &3, accessing ejb module from web module[2] is not available because they are in different application instances, thus, the relevant stub class files generated in app1, can not be seen (in class loader of app2) in web module[2] in app2.
Thanks pai!
So, if web module[2] want to access ejb module in app1, adding it into ear of app1 should be a simple solution.