Please....Help.

I am A newbie in java...Have a bit of programming expirience.
now, Im creating a distributed app. And im trying to create the client side first.
So: I created a GUI Prompt for entering a security code to get into my virtual Room.

But my most important question now is...Assuming the virtual room already exists, how do I execute it from the acceptance of the right code ? which is itself an application. I suppose the most obvious question is...How do I launch an Application from an already launched application ?

Language: Java OO
Thank You for your time.

java RMI?

If you mean Remote Method Invocation, Yes...

Cos I have this GUI DialPad...For Entering a code combination. and i will like it to launch the next app on the acceptance of the correct code.
Thank you :)