code: @Override
  	public void update() {
  		synchronized (this) {
  			long currentTime = System.currentTimeMillis();
  			if (currentTime - lastUpdateTime > updateInterval) {
  				lastUpdateTime = currentTime;
  				fetchMetrics();
  			}
  		}
  	}
docs: This method can be used to signal this MetricFetcher that the metrics are still in use and should be updated.