postProcess.startDocument();
postProcess.startElement("", "diffreport", "diffreport",new AttributesImpl());
addDiffCss(postProcess);
postProcess.startElement("", "diff", "diff", new AttributesImpl());
final HtmlSaxDiffOutput output = new HtmlSaxDiffOutput(postProcess,prefix);
final HTMLDiffer differ = new HTMLDiffer(output);
differ.diff(rightComparator, leftComparator);
postProcess.endElement("", "diff", "diff");