Why not run it from the command-line? You are better off not using an IDE at this stage, if possible.
I have found an Eclipse Tutorial; that might help.
When you open the new class wizard in Eclipse, it asks for the name of the class, and also it superclass; if you put "Employee" in the superclass box, it will automaticaly add extends Employee to your source code.
I think this thread might sit better on our IDEs forum, so shall move it there.