[Q] Plug-in development

Hello,

I'm looking for any information how I can achieve this:

I'd like to develop a plugin or what's needed to modify the behavior of Netbeans editor.  For example, in IDE Java code editor, if I press certain keys (e.g. like shortcut key Ctrl-E,X,P or something), I want to insert certain text, or certain sub-menu pops up.

Can anyone please point me where I should look/read/learn how I can achieve this?

Thanks.