@SuppressWarnings("unchecked")
 @Override
 public void serviceStop() throws Exception {
   ((AbstractYarnScheduler<SchedulerApplicationAttempt, SchedulerNode>) scheduler).stop();
   super.serviceStop();
 }
 @SuppressWarnings("unchecked")
 @Override
 public void serviceInit(Configuration conf) throws Exception {
   ((AbstractYarnScheduler<SchedulerApplicationAttempt, SchedulerNode>) scheduler).init(conf);
   super.serviceInit(conf);
 }