code: public <T extends IEntity> void downloadAsync(T entity, CallbackHandler callbackHandler) throws FMSException {
  
          IntuitMessage intuitMessage = prepareDownload(entity);
  
          //set callback handler
          intuitMessage.getRequestElements().setCallbackHandler(callbackHandler);
  
          //execute async interceptors
          executeAsyncInterceptors(intuitMessage);
      }
docs: Method to download the file for the given entity id in asynchronous fashion
  
  @param entity
  the entity
  @param callbackHandler
  the callback handler
  @throws FMSException
  throws FMSException