public void TestMultiplySinks()
        {
            var sink2 = new DigitalClock(_source);
            _source.RegisterObserver(sink2);

            _source.SetTime(1,2,3);

            AssertSinkEquals(_sink, 1,2,3);
            AssertSinkEquals(sink2, 1, 2, 3);
        }
 private void AssertSinkEquals(DigitalClock sink, int hours, int minutes, int seconds)
 {
     Assert.AreEqual(hours, sink.Hours);
     Assert.AreEqual(minutes, sink.Minutes);
     Assert.AreEqual(seconds, sink.Seconds);
 }
 public void TearDown()
 {
     _sink = null;
     _source = null;
 }
 public void SetUp()
 {
     _source = new Clock();
     _sink = new DigitalClock(_source);
     _source.RegisterObserver(_sink);
 }