question: public void update ( ) { if ( bgIsOpaque ) { int w = Math . max ( getSize ( ) . width , minWidth ) ; int h = Math . max ( getSize ( ) . height , minHeight ) ; offScr = createImage ( w , h ) ; if ( offScr == null ) return ; Graphics g = offScr . getGraphics ( ) ; drawInto ( g ) ; repaint ( ) ; g . dispose ( ) ; } else { repaint ( ) ; } }
target:  Updates all changes in areas state and repaints component.