code: private void checkAsXML(InputSource is) throws IOException, SAXException {
          xmlParser.setCharacterHandler(sourceCode);
          sourceCode.initialize(is);
          try {
              xmlReader.parse(is);
          } catch (SAXParseException e) {
          } catch (FatalSAXException e) {
          }
      }
docs: /* *
  Parses a document with the XML parser and validates it.