docs: static List<Integer> parseClientHello(ByteBuffer source)
              throws SSLException {
  
          ByteBuffer input = source.duplicate();
  
          // Do we have a complete header?
          if (isIncompleteHeader(input)) {
              throw new BufferUnderflowException();
          }
          // Is it a handshake message?
          byte firstByte = input.get();
          byte secondByte = input.get();
          byte thirdByte = input.get();
  
          if ((firstByte & 0x80) != 0 && thirdByte == 0x01) {
              // looks like a V2ClientHello, we ignore it.
              return null;
          } else if (firstByte == 22) {   // 22: handshake record
              if (secondByte == 3 && thirdByte >= 1 && thirdByte <= 3) {
                  return exploreTLSRecord(input,
                          firstByte, secondByte, thirdByte);
              }
          }
          return null;
      }