} else {
                        logger.warn("id is empty: {}", memberOf);
                    }
                    final String[] names = fessConfig.getAzureAdPermissionFields();
                    final boolean useDomainServices = fessConfig.isAzureAdUseDomainServices();
                    for (final String name : names) {

    }

    default int getLtrWindowSize() {
        return getSystemPropertyAsInt(Constants.LTR_WINDOW_SIZE_PROPERTY, 100);
    }

    default String[] getAzureAdPermissionFields() {
        return split(getSystemProperty("aad.permission.fields", "mail"), ",")
                .get(stream -> stream.filter(StringUtil::isNotBlank).map(String::trim).toArray(n -> new String[n]));
    }