You may develop using an IDE (Integrated Development Environment) but your final product may not have any residual dependency upon that.
The new assignment states:
You are permitted to use any IDE tool you choose, but you must not submit any code that is not your own work. The final program must have no dependencies on any libraries other than those of the Java 2 Platform.
In general I would recommend against using any of the JBuilder wizards (including the designer for the screens). They can sometimes create a dependancy on JBuilder libraries, and the code generated is "not your own work". But if you just want to use JBuilder's code higlighting / code completion / backups of last 'x' files / integrated debugger then you should be OK. Regards, Andrew