docs: private static boolean containsAddress(final InetAddress network, final InetAddress netmask, final InetAddress ip) {
          LOGGER.debug("Checking IP address: [{}] in [{}] by [{}]", ip, network, netmask);
          val networkBytes = network.getAddress();
          val netmaskBytes = netmask.getAddress();
          val ipBytes = ip.getAddress();
          /* check IPv4/v6-compatibility or parameters: */
          if (networkBytes.length != netmaskBytes.length || netmaskBytes.length != ipBytes.length) {
              LOGGER.debug("Network address [{}], subnet mask [{}] and/or host address [{}]" + " have different sizes! (return false ...)", network, netmask, ip);
              return false;
          }
          /* Check if the masked network and ip addresses match: */
          for (var i = 0; i < netmaskBytes.length; i++) {
              val mask = netmaskBytes[i] & HEX_RIGHT_SHIFT_COEFFICIENT;
              if ((networkBytes[i] & mask) != (ipBytes[i] & mask)) {
                  LOGGER.debug("[{}] is not in [{}]/[{}]", ip, network, netmask);
                  return false;
              }
          }
          LOGGER.debug("[{}] is in [{}]/[{}]", ip, network, netmask);
          return true;
      }