question: @ Override protected void paintComponent ( final Graphics g ) { super . paintComponent ( g ) ; if ( hasFocus ( ) ) { g . setColor ( JBColor . black ) ; DarculaUIUtil . paintFocusRing ( g , 0 , 0 , getWidth ( ) , getHeight ( ) ) ; } }
target:  We are overriding this method to paint a focus rectangle around the control.