public synchronized void shutdown() {
    if (isShutdown()) {
      return;
    }
    scheduler.shutdownNow();
    LOG.info("Chore service for: {} had {} on shutdown", coreThreadPoolPrefix,
      scheduledChores.keySet());
    cancelAllChores(true);
    scheduledChores.clear();
    choresMissingStartTime.clear();
  }
Shut down the service. Any chores that are scheduled for execution will be cancelled. Any
chores in the middle of execution will be interrupted and shutdown. This service will be
unusable after this method has been called (i.e. future scheduling attempts will fail).
<p/>
Notice that, this will only clean the chore from this ChoreService but you could still schedule
the chore with other ChoreService.
hbase-common/src/main/java/org/apache/hadoop/hbase/ChoreService.java