*  @param expression A valid XPath string.
     *  @return A XPathNodes, should never be null.
     *
     * @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);
    }

    /**

     */
    public PasswordBasedExtractor() {
        super();
    }

    /**
     * Adds a password for files matching the given regular expression pattern.
     * @param regex the regular expression pattern to match against URLs or resource names
     * @param password the password to use for matching files
     */
    public void addPassword(final String regex, final String password) {

		</antcall>
		<!-- lang-expression -->
		<antcall target="install.module">
			<param name="repo.url" value="${maven.release.repo.url}" />
			<param name="module.groupId" value="org/codelibs/opensearch/module" />
			<param name="module.name.prefix" value="" />
			<param name="module.name" value="lang-expression" />
			<param name="module.version" value="${opensearch.version}" />

    boolean match(String url);

    /**
     * Add an url pattern as a target.
     *
     * @param urlPattern Regular expression that is crawled
     */
    void addInclude(String urlPattern);

    /**
     * Add an url pattern as a non-target.
     *
     * @param urlPattern Regular expression that is not crawled
     */
    void addExclude(String urlPattern);

    /**

                        logger.debug("Path {} matches the exclude path expression {} on {} of label.", path, excludedPaths, value);
                    }
                    return false;
                }
                if (logger.isDebugEnabled()) {
                    logger.debug("Path {} does not match the exclude path expression {} on {} of label.", path, excludedPaths, value);
                }

    /** HTTP header name for robots tag */
    private static final String X_ROBOTS_TAG = "X-Robots-Tag";

    /** XPath expression for extracting thumbnail content from meta tags */
    private static final String META_NAME_THUMBNAIL_CONTENT = "//META[@name=\"thumbnail\" or @name=\"THUMBNAIL\"]/@content";

    /** XPath expression for extracting Open Graph image content from meta tags */

        boostExpression = expression;
    }

    /**
     * Gets the current match expression.
     *
     * @return the match expression string
     */
    public String getMatchExpression() {
        return matchExpression;
    }

    /**
     * Sets the match expression used to determine if documents should be boosted.
     *
     * @param expression the match expression string
     */

    /**
     * Adds a client with a regular expression pattern.
     * @param regex The regular expression to match URLs.
     * @param client The CrawlerClient instance.
     */
    public void addClient(final String regex, final CrawlerClient client) {
        if (StringUtil.isBlank(regex)) {
            throw new CrawlerSystemException(

     * @return a list of compiled regular expression patterns representing the URLs to include
     */
    List<Pattern> getIncludeUrlPatternList(String sessionId);

    /**
     * Retrieves a list of URL patterns to be excluded for a given session.
     *
     * @param sessionId the identifier of the session for which to retrieve the exclude URL patterns
     * @return a list of compiled regular expression patterns representing the URLs to be excluded

    }

    /**
     * Adds a regular expression rule for the specified field.
     * @param key the field name to match against
     * @param regex the regular expression pattern
     */
    public void addRule(final String key, final String regex) {
        regexMap.put(key, Pattern.compile(regex));
    }

    /**
     * Adds a compiled regular expression rule for the specified field.