code: public void marshall(Handshake handshake, ProtocolMarshaller protocolMarshaller) {
  
          if (handshake == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(handshake.getId(), ID_BINDING);
              protocolMarshaller.marshall(handshake.getArn(), ARN_BINDING);
              protocolMarshaller.marshall(handshake.getParties(), PARTIES_BINDING);
              protocolMarshaller.marshall(handshake.getState(), STATE_BINDING);
              protocolMarshaller.marshall(handshake.getRequestedTimestamp(), REQUESTEDTIMESTAMP_BINDING);
              protocolMarshaller.marshall(handshake.getExpirationTimestamp(), EXPIRATIONTIMESTAMP_BINDING);
              protocolMarshaller.marshall(handshake.getAction(), ACTION_BINDING);
              protocolMarshaller.marshall(handshake.getResources(), RESOURCES_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }
docs: Marshall the given parameter object.