if (anchorList.isEmpty()) {
            return null;
        }

        final Set<RequestData> childUrlSet = new LinkedHashSet<>();
        for (final String anchor : anchorList) {
            childUrlSet.add(RequestDataBuilder.newRequestData().get().url(anchor).build());
        }
        return childUrlSet;
    }

    protected Set<RequestData> getChildUrlSet(final SearchEngineClient searchEngineClient, final String id) {

        // created
        final Date now = systemHelper.getCurrentTime();
        putResultDataBody(dataMap, fessConfig.getIndexFieldCreated(), now);
        // TODO anchor
        putResultDataBody(dataMap, fessConfig.getIndexFieldAnchor(), StringUtil.EMPTY);
        // mimetype
        putResultDataBody(dataMap, fessConfig.getIndexFieldMimetype(), mimeType);

    /** The key of the configuration. e.g. last_modified */
    String INDEX_FIELD_last_modified = "index.field.last_modified";

    /** The key of the configuration. e.g. anchor */
    String INDEX_FIELD_ANCHOR = "index.field.anchor";

    /** The key of the configuration. e.g. segment */
    String INDEX_FIELD_SEGMENT = "index.field.segment";

    /** The key of the configuration. e.g. role */

        defaultDataMap.put(fessConfig.getIndexFieldMimetype(), mimeType);
        // title
        // content
        // cache
        // digest
        // host
        // site
        // url
        // anchor
        // content_length
        // last_modified
        // id
        // virtual_host
        defaultDataMap.put(fessConfig.getIndexFieldVirtualHost(),

        // created
        final Date now = systemHelper.getCurrentTime();
        putResultDataBody(dataMap, fessConfig.getIndexFieldCreated(), now);
        // anchor
        putResultDataBody(dataMap, fessConfig.getIndexFieldAnchor(), getAnchorList(document, responseData));
        // mimetype
        putResultDataBody(dataMap, fessConfig.getIndexFieldMimetype(), mimeType);