code: public void marshall(StartSelector startSelector, ProtocolMarshaller protocolMarshaller) {
  
          if (startSelector == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(startSelector.getStartSelectorType(), STARTSELECTORTYPE_BINDING);
              protocolMarshaller.marshall(startSelector.getAfterFragmentNumber(), AFTERFRAGMENTNUMBER_BINDING);
              protocolMarshaller.marshall(startSelector.getStartTimestamp(), STARTTIMESTAMP_BINDING);
              protocolMarshaller.marshall(startSelector.getContinuationToken(), CONTINUATIONTOKEN_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }
docs: Marshall the given parameter object.