public static String INSPECT_QUERY_PARAM = "inspect";
public static boolean DEBUG_ENABLED = true;
public static HtmlCanvas createCanvas(HttpServletRequest request, HttpServletResponse response, Writer out) {
HtmlCanvas html = null;
// detect debug request
if (DEBUG_ENABLED && (request.getParameter(INSPECT_QUERY_PARAM) != null)) {
html = new DebugHtmlCanvas(request, response, out);
} else {
html = new HtmlServletCanvas(request, response, out);