code: public static DnsOpCode valueOf(int b) {
          switch (b) {
          case 0x00:
              return QUERY;
          case 0x01:
              return IQUERY;
          case 0x02:
              return STATUS;
          case 0x04:
              return NOTIFY;
          case 0x05:
              return UPDATE;
          }
  
          return new DnsOpCode(b);
      }
docs: Returns the {@link DnsOpCode} instance of the specified byte value.