question: @ Override public void drawOutline ( Graphics2D g2 , CategoryPlot plot , Rectangle2D dataArea ) { float x0 = ( float ) dataArea . getX ( ) ; float x1 = x0 + ( float ) Math . abs ( this . xOffset ) ; float x3 = ( float ) dataArea . getMaxX ( ) ; float x2 = x3 - ( float ) Math . abs ( this . xOffset ) ; float y0 = ( float ) dataArea . getMaxY ( ) ; float y1 = y0 - ( float ) Math . abs ( this . yOffset ) ; float y3 = ( float ) dataArea . getMinY ( ) ; float y2 = y3 + ( float ) Math . abs ( this . yOffset ) ; GeneralPath clip = new GeneralPath ( ) ; clip . moveTo ( x0 , y0 ) ; clip . lineTo ( x0 , y2 ) ; clip . lineTo ( x1 , y3 ) ; clip . lineTo ( x3 , y3 ) ; clip . lineTo ( x3 , y1 ) ; clip . lineTo ( x2 , y0 ) ; clip . closePath ( ) ; Stroke outlineStroke = plot . getOutlineStroke ( ) ; Paint outlinePaint = plot . getOutlinePaint ( ) ; if ( ( outlineStroke != null ) && ( outlinePaint != null ) ) { g2 . setStroke ( outlineStroke ) ; g2 . setPaint ( outlinePaint ) ; g2 . draw ( clip ) ; } }
target:  Draws the outline for the plot.