*/
protected void drawDomainGridlines(Graphics2D g2, Rectangle2D dataArea) {
// draw the domain grid lines, if any...
if (isDomainGridlinesVisible()) {
CategoryAnchor anchor = getDomainGridlinePosition();
RectangleEdge domainAxisEdge = getDomainAxisEdge();
Stroke gridStroke = getDomainGridlineStroke();
Paint gridPaint = getDomainGridlinePaint();
if ((gridStroke != null) && (gridPaint != null)) {
// iterate over the categories