@Override
    public List<AnalyticJob> fetchJobsForBackfill(long startTime, long endTime) throws Exception {
      // Verify whether jobs were backfilled based on lowest ts of apps retrieved from RM and backfill ts in DB.
      if ((startTime == _backfillTs - ElephantRunner.BACKFILL_BUFFER_TIME) && (endTime == _lowestTsFromRM)) {
        _jobsFetchedFlag = true;
      }
      return _backfillJobs;
    }
Tests backfilling of jobs when Dr.Elephant comes up.
test/com/linkedin/drelephant/BackfillTest.java