code: public boolean isOnline() {
  		LOG.debug("Checking online status for {} at {}", getName(), getURL());
  		try {
  			return client
  				.execute(new HttpHead(toURI(getURL())))
  				.getStatusLine()
  				.getStatusCode() != 404;
  		} catch (Exception e) {
  			return false;
  		}
  	}
docs: This method will send HTTP HEAD request to the camera URL to check whether it's online or
  offline. It's online when this request succeed and it's offline if any exception occurs or
  response code is 404 Not Found.
  
  @return True if camera is online, false otherwise