resultBuf.append(e.getMessage()).append("\n");
        }

        // purge search logs
        try {
            final int days = ComponentUtil.getFessConfig().getPurgeSearchLogDay();
            if (days >= 0) {
                searchLogService.deleteBefore(days);
            } else {
                resultBuf.append("Skipped to purge search logs.\n");
            }

        form.popularWord = fessConfig.isWebApiPopularWord() ? Constants.TRUE : Constants.FALSE;
        form.csvFileEncoding = fessConfig.getCsvFileEncoding();
        form.purgeSearchLogDay = fessConfig.getPurgeSearchLogDay();
        form.purgeJobLogDay = fessConfig.getPurgeJobLogDay();
        form.purgeUserInfoDay = fessConfig.getPurgeUserInfoDay();
        form.purgeByBots = fessConfig.getPurgeByBots();

    }

    default void setPurgeSearchLogDay(final int value) {
        setSystemPropertyAsInt(Constants.PURGE_SEARCH_LOG_DAY_PROPERTY, value);
    }

    default int getPurgeSearchLogDay() {
        return getSystemPropertyAsInt(Constants.PURGE_SEARCH_LOG_DAY_PROPERTY, DfTypeUtil.toInteger(Constants.DEFAULT_PURGE_DAY));
    }

    default void setPurgeJobLogDay(final int value) {