question: @ Override public CategoryItemRendererState initialise ( Graphics2D g2 , Rectangle2D dataArea , CategoryPlot plot , int rendererIndex , PlotRenderingInfo info ) { Rectangle2D adjusted = new Rectangle2D . Double ( dataArea . getX ( ) , dataArea . getY ( ) + getYOffset ( ) , dataArea . getWidth ( ) - getXOffset ( ) , dataArea . getHeight ( ) - getYOffset ( ) ) ; CategoryItemRendererState state = super . initialise ( g2 , adjusted , plot , rendererIndex , info ) ; return state ; }
target:  Initialises the renderer and returns a state object that will be passed to subsequent calls to the drawItem method.  This method gets called once at the start of the process of drawing a chart.