Keybindings are specified in yet another folder in the system filesystem. The folder Shortcuts/ contains .instance files? or .shadow files? (shadow files are like symlinks to another file in the system fs) - these map to Actions.
The file name for the action (.instance or .shadow) file in Shortcuts/ is used to specify what keys are bound. This is done using an emacs-like syntax for specifying keybindings - e.g., CA-P equals Ctrl-Alt-P.
There are special modifier characters which map to Command on Mac and Ctrl on PC, Ctrl on Mac and Alt on PC. You should use those unless you're really sure your app will never be used on macintosh or never be used by someone with a non-English macintosh.
Source: NetBeans FAQ