code: public void stop() {
  		if (running.compareAndSet(true, false)) {
  
  			executor.shutdown();
  			while (!executor.isTerminated()) {
  				try {
  					executor.awaitTermination(100, TimeUnit.MILLISECONDS);
  				} catch (InterruptedException e) {
  					return;
  				}
  			}
  
  			LOG.debug("Webcam updater has been stopped");
  		} else {
  			LOG.debug("Webcam updater is already stopped");
  		}
  	}
docs: Stop updater.