To see the operation just run the NameService class that will maintain a thread in the air and then run the CalculatorClient class Code taken from -https://github.com/elton-oliveira/rmi-example.

http://docs.oracle.com/javase/1.5.0/docs/guide/rmi/hello/hello-world.html

1. Define the remote interface, interface Hi extends Remote

2. Implement the server to the interface defined in step 1

3. Create the client