*
     * @see org.codelibs.fess.crawler.entity.UrlQueue#getDepth()
     */
    @Override
    public Integer getDepth() {
        return depth;
    }

    /*
     * (non-Javadoc)
     *
     * @see org.codelibs.fess.crawler.entity.UrlQueue#setDepth(java.lang.Integer)
     */
    @Override
    public void setDepth(final Integer depth) {
        this.depth = depth;
    }

    /*

     * Retrieves the depth of the URL in the queue.
     *
     * @return the depth of the URL as an Integer.
     */
    Integer getDepth();

    /**
     * Sets the depth of the URL in the queue.
     *
     * @param depth the depth to set, represented as an Integer.
     */
    void setDepth(Integer depth);

    /**
     * Returns the last modified timestamp of the URL in the queue.
     *

        urlQueue.setDepth(1);
        urlQueue.setMethod("GET");
        urlQueue.setSessionId("id1");
        urlQueue.setUrl("http://www.id1.com/");

        urlQueueService.insert(urlQueue);

        final OpenSearchUrlQueue urlQueue2 = new OpenSearchUrlQueue();
        urlQueue2.setCreateTime(System.currentTimeMillis());
        urlQueue2.setDepth(1);
        urlQueue2.setMethod("GET");

            final UrlQueueImpl<Long> urlQueue = new UrlQueueImpl<>();
            urlQueue.setSessionId(sessionId);
            urlQueue.setMethod(Constants.GET_METHOD);
            urlQueue.setUrl(url);
            urlQueue.setDepth(0);
            urlQueue.setCreateTime(SystemUtil.currentTimeMillis());
            urlQueueList.add(urlQueue);
        }
    }

    /*
     * (non-Javadoc)
     *
     * @see