code: public void getResourceAsFile(String path, String fileType, OutputStream outputStream)
              throws SmartsheetException {
          Util.throwIfNull(outputStream, fileType);
  
          HttpRequest request;
          request = createHttpRequest(this.getSmartsheet().getBaseURI().resolve(path), HttpMethod.GET);
          request.getHeaders().put("Accept", fileType);
  
          try {
              HttpResponse response = getSmartsheet().getHttpClient().request(request);
  
              switch (response.getStatusCode()) {
                  case 200:
                      try {
                          copyStream(response.getEntity().getContent(), outputStream);
                      } catch (IOException e) {
                          throw new SmartsheetException(e);
                      }
                      break;
                  default:
                      handleError(response);
              }
          } finally {
              getSmartsheet().getHttpClient().releaseConnection();
          }
      }
docs: Get a sheet as a file.
  
  Exceptions:
  - InvalidRequestException : if there is any problem with the REST API request
  - AuthorizationException : if there is any problem with the REST API authorization(access token)
  - ResourceNotFoundException : if the resource can not be found
  - ServiceUnavailableException : if the REST API service is not available (possibly due to rate limiting)
  - SmartsheetRestException : if there is any other REST API related error occurred during the operation
  - SmartsheetException : if there is any other error occurred during the operation
  
  @param path the path
  @param fileType the output file type
  @param outputStream the OutputStream to which the file will be written
  @return the report as file
  @throws SmartsheetException the smartsheet exception