docs: public void marshall(Landmark landmark, ProtocolMarshaller protocolMarshaller) {
  
          if (landmark == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(landmark.getType(), TYPE_BINDING);
              protocolMarshaller.marshall(landmark.getX(), X_BINDING);
              protocolMarshaller.marshall(landmark.getY(), Y_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }