question: @ Override public void handleMouseMoved ( ChartCanvas canvas , MouseEvent e ) { if ( ! canvas . isTooltipEnabled ( ) ) { return ; } String text = getTooltipText ( canvas , e . getX ( ) , e . getY ( ) ) ; canvas . setTooltip ( text , e . getScreenX ( ) , e . getScreenY ( ) ) ; }
target:  Handles a mouse moved event by updating the tooltip.