@Override
  public Instant getWatermarkThatGuaranteesFiring(BoundedWindow window) {
    return BoundedWindow.TIMESTAMP_MAX_VALUE;
  }
@Test
  public void testFireDeadline() throws Exception {
    assertEquals(
        BoundedWindow.TIMESTAMP_MAX_VALUE,
        underTest.getWatermarkThatGuaranteesFiring(
            new IntervalWindow(new Instant(0), new Instant(10))));
  }