code: public void getFileFromTask(String jobId, String taskId, String fileName, Iterable<BatchClientBehavior> additionalBehaviors, OutputStream outputStream) throws BatchErrorException, IOException {
          FileGetFromTaskOptions options = new FileGetFromTaskOptions();
          BehaviorManager bhMgr = new BehaviorManager(this.customBehaviors(), additionalBehaviors);
          bhMgr.applyRequestBehaviors(options);
  
          this.parentBatchClient.protocolLayer().files().getFromTask(jobId, taskId, fileName, options, outputStream);
      }
docs: Downloads the specified file from the specified task's directory on its compute node.
  
  @param jobId The ID of the job containing the task.
  @param taskId The ID of the task.
  @param fileName The name of the file to download.
  @param additionalBehaviors A collection of {@link BatchClientBehavior} instances that are applied to the Batch service request.
  @param outputStream A stream into which the file contents will be written.
  @throws BatchErrorException Exception thrown when an error response is received from the Batch service.
  @throws IOException Exception thrown when there is an error in serialization/deserialization of data sent to/received from the Batch service.