The getKeyChar method always returns a valid Unicode character or
CHAR_UNDEFINED. Character input is reported by KEY_TYPED events:
KEY_PRESSED and KEY_RELEASED events are not necessarily associated with
character input. Therefore, the result of the getKeyChar method is
guaranteed to be meaningful only for KEY_TYPED events.

For key pressed and key released events, the getKeyCode method returns
the event's keyCode. For key typed events, the getKeyCode method always
returns VK_UNDEFINED.