code: private void initDocumentParser() throws ParserConfigurationException {
  
      DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
  
      docBuilderFactory.setNamespaceAware(false);
      docBuilderFactory.setValidating(true);
  
      docBuilderFactory.setAttribute(
          "http://java.sun.com/xml/jaxp/properties/schemaLanguage",
          "http://www.w3.org/2001/XMLSchema");
  
      docBuilderFactory.setAttribute(
          "http://java.sun.com/xml/jaxp/properties/schemaSource", resolveSchemaSource());
  
      docBuilder = docBuilderFactory.newDocumentBuilder();
  
      docBuilder.setErrorHandler(this);
  
      xpath = XPathFactory.newInstance().newXPath();
    }
docs: Initializes the XML parser.
  
  @throws ParserConfigurationException