The global keymap (get Keymap from Lookup) is a master keymap for the whole IDE, and like all keymaps accepts only one action per binding. If you want multiple actions to be run, you must create a "wrapper" action that runs them all in turn (or in parallel).
You may bind a key differently in different windows, by using the normal Swing techniques of binding keystrokes to components. In fact, some work went into implementing the global map so that it would work across arbitrary components; it is overridden by local bindings, such as navigation keys on dialogs or Explorer trees, or various editing keys in the Editor.
Before you bind a key performing a high-level specific action, such as Ctrl-N for New File, to a different action in a local component (e.g. window), think carefully whether this is really the right approach. In many cases the UI of your extension and the IDE as a whole will be better served by leaving the key binding alone, and instead providing an appropriate cookie, action performer, or other callback associated with your component, so that the action (and potentially other code unknown to you) will function naturally. If you must rebind a global key, consider whether it is appropriate to determine the current key binding for the action (if any) in the global keymap, and use this keystroke to rebind - so user customizations will remain intact.
CallbackSystemActions such as Find or Delete can easily have different bindings in each component, using ActionMap.
Source: NetBeans FAQ