code: private TaskID maskTaskID(TaskID taskId) {
      JobID jobId = new JobID();
      return new TaskID(jobId, taskId.isMap(), taskId.getId());
    }
docs: Mask the job ID part in a {@link TaskID}.
  
  @param taskId
  raw {@link TaskID} read from trace
  @return masked {@link TaskID} with empty {@link JobID}.