code: @Override
      public void removedService(ServiceReference<SessionDestroyedListener> serviceReference,
              SessionDestroyedListener object) {
          if (LOGGER.isDebugEnabled()) {
              LOGGER.debug("Listener [" + serviceReference + "] has been removed.");
          }
  
          final SessionDestroyedListener listener = context.getService(serviceReference);
          handler.removeListener(listener);
      }
docs: {@inheritDoc}
  
  Handle removed service.
  @see ServiceTracker#removedService(ServiceReference,Object)