VersionControlService throwing Remote exception

Hello Everyone,

I am new to Windchill customization. I am using eclipse for code writing, I have configured method server with eclipse. Problem is, I am able to write and debug normal APIs based code but when I use any service related API like VersionControlService  I am getting exception.

like below.

Exception in thread ``main`` wt.util.WTRemoteException: unable to invoke remote method; nested exception is :

            java.rmi.ServerRuntimeException: Server exception; nested exception is:

             java.lang.NullpointerException

              .....

             ......

I am calling method using  RemoteMethodServer API and invoking class using invoke method.

can any body guide me what wrong I am doing while running the code.

Windchill and eclipse are running on same machine.