public void addListener(final StatisticsListener listener) {
    if (listener == null) {
      throw new NullPointerException("StatisticsListener is null");
    }
    synchronized (mutex) {
      if (!listeners.contains(listener)) {
        listeners.add(listener);
        getStatMonitorHandler().addMonitor(this);
      }
    }
  }
TODO: define another addStatistic for StatisticDescriptor which will enable static monitoring
that will fire for all instances even ones that may not yet be created at the time this monitor
is defined

@since GemFire 7.0
geode-core/src/main/java/org/apache/geode/internal/statistics/StatisticsMonitor.java