@Override
      public void rejectedExecution(Runnable runnable, ThreadPoolExecutor e) {
        LOG.debug("Re-comparison execution rejected. Running in main thread.");
        context.getCounter(Counters.MAIN_THREAD_RECOMPARES).increment(1);
        // will run in the current thread
        super.rejectedExecution(runnable, e);
      }
Sets up the actual job.
@param conf The current configuration.
@param args The command line parameters.
@return The newly created job.
@throws java.io.IOException When setting up the job fails.
hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/replication/VerifyReplication.java