code: public static byte[] getRawAddress(final String ipv4Address) {
          final Matcher m = IPV4_ADDRESS.matcher(ipv4Address);
          if (!m.find()) {
              return null;
          }
          final byte[] addr = new byte[4];
          for (int i = 0; i < 4; i++) {
              final int intVal = Integer.parseInt(m.group(i+1)) & 0x00ff;
              addr[i] = (byte) intVal;
          }
          return addr;
      }
docs: Converts an IPv4 address to raw bytes, returning a byte[4], or null if the input is malformed.
  
  @param ipv4Address The string representation of an ipv4 address.
  @return A {@code byte[]} containing the parts of the v4 ip address.