@Override
 public Document modifyDocument(Document document, String value) {
   if (value == null || value.isEmpty()) {
     return document;
   }
   try {
     Node node = getNodeFromXpath(document);
     node.setTextContent(value);
   } catch (XPathExpressionException ex) {
     ex.fillInStackTrace();
     Logger.getLogger(HeritrixParameterValueModifier.class.getName()).warn(ex.getMessage());
   }
   return document;
 }