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J2EE Client Application Runtime error

Posted on 2001-08-21
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Last Modified: 2013-11-24
I have just started how to do these so called EJBs. I wrote my simple ejb. and the client application as well. deployed the app.
now i tried to run the application and got the following erro which is very confusing to a beginner like me so please help:
javax.naming.InitialContext Exception: Need to specify class name in environment or system property or as an applet parameter or in an application resource file: java.naming.factory.initial
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Question by:TinasheC
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Jim Cakalic earned 15 total points
ID: 6411205
Because EJBs operate in a distributed environment, EJB clients need to "find" the EJB objects by performing a naming lookup. The InitialContext is the starting point for all naming lookups.

When constructing an InitialContext, you need to supply various parameters of the environment in which naming operations are to be performed. There are typically two that must be specified: INITIAL_CONTEXT_FACTORY (property named java.naming.factory.initial) and PROVIDER_URL (property name java.naming.provider.url).

If you use the no-arg constructor of javax.naming.InitialContext, then you can usually specify these as System properties. One way to do that is to use the -D option when running the java command. For example:

java -Djava.naming.provider.url=iiop://localhost:900/ MyApp

will set the java.naming.provider.url as a System property (a property accessed through the System.getProperty class method).

Alternatively, you can specify the properties by using the InitialContext constructor that takes a Hashtable argument. This is the preferred method since not all naming properties may be set as System properties. Code to do this looks something like:

    java.util.Hashtable environment = new java.util.Hashtable(2);
    environment.put(javax.naming.Context.PROVIDER_URL, "iiop://webspherehost:900/");
    environment.put(javax.naming.Context.INITIAL_CONTEXT_FACTORY, "com.ibm.ejs.ns.jndi.CNInitialContextFactory");
    javax.naming.InitialContext initContext = new javax.naming.InitialContext(environment);

In this case, I'm setting the provider URL to reference a specific host in my environment (where my application server is running) and the context factory to an IBM WebSphere class. The values that you specify in your environment will be different.

You can find more complete information on setting naming properties at
http://java.sun.com/j2ee/j2sdkee/techdocs/api/javax/naming/package-summary.html
http://java.sun.com/j2ee/j2sdkee/techdocs/api/javax/naming/InitialContext.html

Best regards,
Jim Cakalic
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Author Comment

by:TinasheC
ID: 6530563
Thanks I have looked into the examples and documentation. Re doing the programs again I have used the runclient tool to run my examples but now I am getting the following error
:
java.lang.NoClassDefFoundError: ConverterHome

it cannot find the home interface.
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