code: public Observable<HierarchicalEntityExtractor> getHierarchicalEntityAsync(UUID appId, String versionId, UUID hEntityId) {
          return getHierarchicalEntityWithServiceResponseAsync(appId, versionId, hEntityId).map(new Func1<ServiceResponse<HierarchicalEntityExtractor>, HierarchicalEntityExtractor>() {
              @Override
              public HierarchicalEntityExtractor call(ServiceResponse<HierarchicalEntityExtractor> response) {
                  return response.body();
              }
          });
      }
docs: Gets information about the hierarchical entity model.
  
  @param appId The application ID.
  @param versionId The version ID.
  @param hEntityId The hierarchical entity extractor ID.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the HierarchicalEntityExtractor object