docs: @Nonnull
    @Nonempty
    public String getRequestValue ()
    {
      final String sCombined = StringHelper.getConcatenatedOnDemand (m_sUserName,
                                                                     HttpBasicAuth.USERNAME_PASSWORD_SEPARATOR,
                                                                     m_sPassword);
      return HttpBasicAuth.HEADER_VALUE_PREFIX_BASIC + " " + Base64.safeEncode (sCombined, HttpBasicAuth.CHARSET);
    }