code: public void marshall(StartDeviceSyncRequest startDeviceSyncRequest, ProtocolMarshaller protocolMarshaller) {
  
          if (startDeviceSyncRequest == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(startDeviceSyncRequest.getRoomArn(), ROOMARN_BINDING);
              protocolMarshaller.marshall(startDeviceSyncRequest.getDeviceArn(), DEVICEARN_BINDING);
              protocolMarshaller.marshall(startDeviceSyncRequest.getFeatures(), FEATURES_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }
docs: Marshall the given parameter object.