public static void addRunningHadoopJob(Dataset dataset, Job job) {
    MRCompactor.RUNNING_MR_JOBS.put(dataset, job);
  }
public static void addRunningHadoopJob ( Dataset dataset , Job job ) { MRCompactor . RUNNING_MR_JOBS . put ( dataset , job ) ; }
Keep track of running MR jobs, so if the compaction is cancelled, the MR jobs can be killed.