code: public static Node getElementB(Node node, XPathExpression xPath) throws XPathExpressionException {
          return getElementsB(node, xPath).item(0);
      }
docs: Helper program: Extracts the specified XPATH expression
  from an XML-String.
  
  @param node  the node
  @param xPath the x path
  @return NodeList
  @throws XPathExpressionException the x path expression exception