Why can't I get an initial context in websphere!?!

Question

I am using WebSphere App Dev v.4.0, and I have written a client application which should call methods from an EJB. But I don't seem to be able to get an initial context no matter what I do. Here is a snippet of the app code and the exception it throws: I will be most grateful if someone could help me out. Thanks Ben.
THE CODE...
try {          
    System.out.println("about to retrieve initial context.");   
    java.util.Properties p = new java.util.Properties();   
    p.put(Context.PROVIDER_URL, "iiop://localhost:901");   
    p.put(Context.INITIAL_CONTEXT_FACTORY, "com.ibm.websphere.naming.WsnInitialContextFactory");   
    InitialContext initContext = new InitialContext(p);
    System.out.println("initial context has been created.");     
}catch (Exception e) {        
    e.printStackTrace();
THE EXCEPTION...
about to retrieve initial context.
javax.naming.NoInitialContextException: Cannot instantiate class: com.ibm.websphere.naming.WsnInitialContextFactory. Root exception is java.lang.ClassNotFoundException: com.ibm.websphere.naming.WsnInitialContextFactory
at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:325)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:380)
at java.lang.ClassLoader.loadClass(ClassLoader.java:257)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:212)
at com.sun.naming.internal.VersionHelper12.loadClass(VersionHelper12.java:46)
at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java:656)
at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java:247)
at javax.naming.InitialContext.init(InitialContext.java:223)
at javax.naming.InitialContext.<init>(InitialContext.java:199)
at BeanClient.main(BeanClient.java:18)

Answer 1

Hi Ben,
As the gurus told in the earlier replies, it is the problem with Class loading.
Make Sure that following jar files are in CLASSPATH. (Assuming C:\Websphere is your websphere installation directory)
J2EE.jar - C:/Websphere/AppServer/lib/J2ee.jar
Websphere.jar - C:/Websphere/AppServer/lib/websphere.jar
Ibmorb.jar - C:/Websphere/AppServer/java/jre/lib/ext/ibmorb.jar
Once you have all these in your CLASSPATH, try running your client application. If you are using Sun JDK you will encounter an error message in the runtime which says like "Service Unavaible.. XXXX Service not found".
When you encounter this problem make sure that your service named XXXX is running and you are calling it appropriately. To find whether a service with name XXXX is running type
>>>>dumpnamespace
at the command prompt. If your service name is listed by dumpnamespace.. your service is running. So there is something wrong with the client code. Proceed to the next step.
In this tep you can use IBM JDK to fix the error. But that might not be the most suitable solution.
Here is how you can run Websphere EJB client programs without IBM JDK.
http://www7b.software.ibm.com/wsdd/downloads/pluggableclient.html
Follow this link and download the Websphere Pluggable application client and follow the instructions given in Readme to install the pluggable application client.
Once you finish installing the pluggable application client, you should be able to run with no problems.
For dwildcat92
I was also under the impression that we SHOULD use IBM JDK to make the client run. But our integration process demanded that the clients be called from Apache Tomcat. Thats how I was forced to find this link
http://www7b.software.ibm.com/wsdd/downloads/pluggableclient.html
Thanks for making me learn guys,
Ravi.