code: @Override
  	protected void drawFirstPassShape(Graphics2D g2, int pass, int series, int item, Shape shape) {
  		g2.setStroke(getItemStroke(series, item));
  		g2.setPaint(getLinePaint(series)); // this line is different from the original
  		g2.draw(shape);
  	}
docs: /*
  Overriding this class since the color of the series needs to be set with getLinePaint
  which makes it possible to set the color for the series in the series instance