code: boolean setGroup(char group[], byte groupstring[])
      {
          if (group != null && groupstring != null && group.length > 0 &&
              groupstring.length > 0) {
              m_groupinfo_ = group;
              m_groupstring_ = groupstring;
              return true;
          }
          return false;
      }
docs: Sets the group name data
  @param group index information array
  @param groupstring name information array
  @return false if there is a data error