docs: public void stop() {
        // This method might get called several times.
        if (stopped) return;
        if (needToUnregister) {
           try {
              unregisterMBeans(resourceDMBeans);
              needToUnregister = false;
           } catch (Exception e) {
              log.problemsUnregisteringMBeans(e);
           }
        }
        stopped = true;
     }