@Override
  public void handleRegionLoss(SystemMemberRegionEvent event) {
    SystemMemberCacheJmxImpl cacheResource = managedSystemMemberCache;

    if (cacheResource != null) {
      ManagedResource cleanedUp = cacheResource.cleanupRegionResources(event.getRegionPath());

      if (cleanedUp != null) {
        MBeanUtils.unregisterMBean(cleanedUp);
      }
    }

    Notification notification = new Notification(NOTIF_REGION_LOST, modelMBean,
        Helper.getNextNotificationSequenceNumber(), Helper.getRegionEventDetails(event));

    notification.setUserData(event.getRegionPath());

    Helper.sendNotification(this, notification);
  }
Implementation should handle loss of region by extracting the details from the given event
object and sending the {@link SystemMemberJmx#NOTIF_REGION_LOST} notification to the connected
JMX Clients. Region Path is set as User Data in Notification. Additionally, it also clears the
ManagedResources created for the region that is lost.

@param event event object corresponding to the loss of a region
geode-core/src/main/java/org/apache/geode/admin/jmx/internal/CacheServerJmxImpl.java