"Add unimplemented methods" feature in the Android Studio

Alt + Enter - on class definition; Ctrl + I - in class body to show list of unimplemented methods. Ctrl + O - in class body to show list of override methods.

On Mac, this is easy with Command + N. This brings up a menu that asks if you want to access the override methods or the interface methods, combining the shortcuts described in the other answers. There is a similar shortcut on Windows, but it's not as convenient.

The source, should they ever change: https://www.jetbrains.com/idea/help/generating-constructors.html

EDIT: or, for interfaces: https://www.jetbrains.com/idea/help/implementing-methods-of-an-interface.html

and supers: https://www.jetbrains.com/idea/help/overriding-methods-of-a-superclass.html

Of course there is. It is called Implement methods or Override Methods. The default shortcut is CTRL-I and CTRL-O. See descrption of Implementing Methods and Overriding Methods.

You can use following shortcuts.

On Windows machine:

• Alt + Enter - on class definition;
• Ctrl + I - in class body to show list of unimplemented methods.

On Mac:

• Option ⌥ + Return - on class definition (Option ⌥ can be also Alt);
• Command ⌘ + I - in class body to show list of unimplemented methods.

There is also useful combination Ctrl + O / Command ⌘ + O - override methods.