code: public synchronized TaskMetricStore getTaskMetricStore(String jobID, String taskID) {
  		JobMetricStore job = jobID == null ? null : jobs.get(jobID);
  		if (job == null || taskID == null) {
  			return null;
  		}
  		return TaskMetricStore.unmodifiable(job.getTaskMetricStore(taskID));
  	}
docs: Returns the {@link ComponentMetricStore} for the given job/task ID.
  
  @param jobID  job ID
  @param taskID task ID
  @return ComponentMetricStore for given IDs, or null if no store for the given arguments exists