if (attrNode != null) {
                    final String attrValue = attrNode.getNodeValue();
                    if (isValidPath(attrValue)) {
                        addChildUrlFromTagAttribute(urlList, url, attrValue, encoding);
                    }
                }
            }
        } catch (final XPathException e) {

     * @param attrValue the attribute value containing the URL
     * @param encoding the character encoding
     */
    @Override
    protected void addChildUrlFromTagAttribute(final List<String> urlList, final URL url, final String attrValue, final String encoding) {
        final String urlValue = attrValue.trim();
        URL childUrl;
        String u = null;
        try {