if (entryDn == null) {
            return null;
        }
        int start = entryDn.toLowerCase(Locale.ROOT).indexOf("cn=");
        if (start == -1) {
            return null;
        }
        start += 3;

        final int end = entryDn.indexOf(',', start);
        final String value = end == -1 ? entryDn.substring(start) : entryDn.substring(start, end);

    protected String scrollForSearch = "1m";

    protected int sizeForDelete = 100;

    protected String scrollForDelete = "1m";

    protected int sizeForUpdate = 100;

    protected String scrollForUpdate = "1m";

    protected int maxConfigSyncStatusRetry = 10;

    protected int maxEsStatusRetry = 60;

    protected String clusterName = "fesen";

        private final HttpServletRequest request;

        private final FessConfig fessConfig;

        private int startPosition = -1;

        private int offset = -1;

        private int pageSize = -1;

        protected JsonRequestParams(final HttpServletRequest request, final FessConfig fessConfig) {
            this.request = request;

    }

    default int getPurgeJobLogDay() {
        return getSystemPropertyAsInt(Constants.PURGE_JOB_LOG_DAY_PROPERTY, DfTypeUtil.toInteger(Constants.DEFAULT_PURGE_DAY));
    }

    default void setPurgeUserInfoDay(final int value) {
        setSystemPropertyAsInt(Constants.PURGE_USER_INFO_DAY_PROPERTY, value);
    }

    default int getPurgeUserInfoDay() {