dataHelper.clearUrlQueueList();
    }

    /*
     * (non-Javadoc)
     *
     * @see org.codelibs.fess.crawler.service.UrlQueueService#offerAll(java.lang.String,
     * java.util.List)
     */
    @Override
    public void offerAll(final String sessionId, final List<UrlQueueImpl<Long>> newUrlQueueList) {
        final Queue<UrlQueueImpl<Long>> urlQueueList = dataHelper.getUrlQueueList(sessionId);

     */
    void deleteAll();

    /**
     * Offers all URL queues.
     *
     * @param sessionId The session ID.
     * @param newUrlQueueList The list of new URL queues.
     */
    void offerAll(String sessionId, List<QUEUE> newUrlQueueList);

    /**
     * Polls a URL queue.
     *
     * @param sessionId The session ID.
     * @return The URL queue.
     */
    QUEUE poll(String sessionId);