if (username == null) {
            value = StringUtil.EMPTY;
        } else if (maxLength >= 0 && username.length() > maxLength) {
            value = LdapUtil.escapeValue(username.substring(0, maxLength));
        } else {
            value = LdapUtil.escapeValue(username);
        }
        return String.format(getSystemProperty(Constants.LDAP_SECURITY_PRINCIPAL, StringUtil.EMPTY), value);
    }