code: @Deprecated
      public void setMonitorNotifier(@Nullable MonitorNotifier notifier) {
          if (determineIfCalledFromSeparateScannerProcess()) {
              return;
          }
          monitorNotifiers.clear();
          if (null != notifier) {
              addMonitorNotifier(notifier);
          }
      }
docs: Specifies a class that should be called each time the <code>BeaconService</code> sees
  or stops seeing a Region of beacons.
  <p/>
  IMPORTANT:  Only one MonitorNotifier may be active for a given application.  If two different
  activities or services set different MonitorNotifier instances, the last one set will receive
  all the notifications.
  
  @param notifier The {@link MonitorNotifier} to register.
  @see MonitorNotifier
  @see #startMonitoringBeaconsInRegion(Region)
  @see Region
  @deprecated replaced by {@link #addMonitorNotifier}