Compiling and Running your programs in java NetBeans

NetBeans allows a very quick code and test cycle. Change the source code and hit the right-facing green arrow in the toolbar to run it. This recompiles only the changed source files.

Clean and Build. The other option you should use is Clean and Build Main Project from the Build menu, or Clean and Build Project from the menu that drops down from a right click on the project. This action removes all object files and recompiles everything. This is important if you rename classes, change static final constants, need a new jar file, and probably in a few other cases. Always use this when you think you've finished a program -- it's better to have the surprises before turning it in to your instructor.

Double-clickable jar file. Build and Clean and Build create a double-clickable jar file in the "dist" directory in your project.