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From Johannes Lietz <rmail-geronimo-u...@rmail.dadabase.de>
Subject Re: Exception in thread "main" java.lang.NullPointerException?
Date Wed, 05 Dec 2007 11:02:14 GMT

EJB is meant to run as a service inside JavaEE-Servers to serve e.g. a web
application inside the server or a number of coupled servers. In general
you won't expose EJBs directly to a standard java remote client
application.

I guess you've done this tutorial already?
http://cwiki.apache.org/GMOxSAMPLES/5-minute-tutorial-on-enterprise-application-development-with-eclipse-and-geronimo.html

Then you've got your working client already, namely the MyServlet.class!

If you want to use them with a plain standard Java application (that's what
I think you want to do?), there's not a defined and easy way to do it.
WebSphere has something like that
(http://www-128.ibm.com/developerworks/websphere/library/techarticles/0409_bhogal/0409_bhogal.html),
but I don't know about Geronimo.

The best way to do what you want to do is to build webservice around your
EJBs, e.g. with SOAP, RMI or similar technologies.

-Johannes


On Tue, 4 Dec 2007 20:48:20 -0800 (PST), beyondjusitn
<beyondjustin@gmail.com> wrote:
> 
> Then, how can I make it to access the remote EJB interface in my
> application
> client? I would really appreciate if you could write an step-by-step
> tutorial to me, of course use eclipse and Geronimo. I'm totally desperate
> now.
> Thanks a lot!
> 
> Johannes Lietz wrote:
>>
>>
>> Simply said: You can't just add a main method to an EJB class and expect
>> it
>> to run in the same way as it would inside an application server.
>>
>> You need the whole infrastructure an application server provides, which
>> does a lot of things behind the scenes. In your class, the server would
>> "magically" instantiate an object for your member remoteBusinessIntf,
>> which
>> will do a sayHello(). In your case remoteBusinessIntf is null, and the
>> error is thrown.
>>
>> -Johannes
>>
>>
>>
>>
> 
> 
> -----
> --
> Best Wishes!
> Justin Tsao
> --
> View this message in context:
>
http://www.nabble.com/Exception-in-thread-%22main%22-java.lang.NullPointerException--tf4943169s134.html#a14165282
> Sent from the Apache Geronimo - Users mailing list archive at Nabble.com.


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