* @throws XPathExpressionException if an XPath expression error occurs.
     */
    public XPathNodes selectNodeList(final Node contextNode, final String expression) throws XPathExpressionException {
        return xPath.evaluateExpression(expression, contextNode, XPathNodes.class);
    }

    /**
     *  Evaluate XPath string to an XObject.
     *  XPath namespace prefixes are resolved from the namespaceNode.

        xPathApi.setNamespaceContext(new DefaultNamespaceContext(doc.getNodeType() == Node.DOCUMENT_NODE ? doc.getDocumentElement() : doc));
        return xPathApi.evaluateExpression(xpath, doc, XPathNodes.class);
    }

    /**
     * Retrieves an XPathAPI instance from the cache or creates a new one.
     * @return An XPathAPI instance.
     */
    protected XPathAPI getXPathAPI() {