The IntelliJ Platform provides the concept of actions.
An action is a class derived from
actionPerformed() method is called when its menu item or toolbar button is selected.
Actions are the most common way for a user to invoke the functionality of your plugin. An action can be invoked from a menu or a toolbar, using a keyboard shortcut, or from the Help | Find Action… lookup.
Actions are organized into groups, which, in turn, can contain other groups. A group of actions can form a toolbar or a menu. Subgroups of the group can form submenus of a menu.
The user can customize all registered actions via Menus and Toolbars settings.
Please see Action System on how to create and register actions in the IDE.