public class Timer {
	private Callback callback;
	public void setCallback(Callback theCallback) {
		callback = theCallback;
	}

	public void run() {
		int tickNum = 0;
		while (true) {
			callback.tick(tickNum);
			tickNum = tickNum + 1;

			// going to sleep
			try {
				Thread.sleep(1000);
			} catch (InterruptedException e) {
			}
		}
	}
}