//---this call will render the chart to an internal BufferedImage, creating all the image map coordinates
axisChart.renderWithImageMap();
//---get the ImageMap information from the chart
ImageMap imageMap = axisChart.getImageMap();
//---set the ImageMap into the HttpServletRequest so can get it out in JSP
httpServletRequest.setAttribute( ChartServlet.IMAGE_MAP, imageMap );
//---set the Chart into the HttpSession so we can stream it in another request