void triggerAction(MemoryUsage usage) {

  {- -------------------------------------------
  (1) MemoryImpl.createNotification() を呼び出して, リスナーに通知を行う.
      ---------------------------------------- -}

                // create and send notification
                MemoryImpl.createNotification(MEMORY_THRESHOLD_EXCEEDED,
                                              pool.getName(),
                                              usage,
                                              getCount());
            }