public class GameTimer
{
	public GameTimer()
	{
		AnimationTimer timer = new AnimationTimer()
		{
		    private long timestamp;
		    private long time = 0;
		    private long fraction = 0;
		    final TextField display = new TextField("0");

		    @Override
		    public void start()
		    {
		        // current time adjusted by remaining time from last run
		        timestamp = System.currentTimeMillis() - fraction;
		        super.start();
		    }

		    @Override
		    public void stop()
		    {
		        super.stop();
		        // save leftover time not handled with the last update
		        fraction = System.currentTimeMillis() - timestamp;
		    }

		    @Override
		    public void handle(long now)
		    {
		        long newTime = System.currentTimeMillis();
		        if (timestamp + 1000 <= newTime) {
		            long deltaT = (newTime - timestamp) / 1000;
		            time += deltaT;
		            timestamp += 1000 * deltaT;
		            display.setText(Long.toString(time));
		        }
		    }
		};
	}
}