public static Instant later(Instant time1, Instant time2) {
        return time1.isAfter(time2) ? time1 : time2;
    }
@Test
    public void later() {
        Instant t1 = Instant.now(); // earlier
        Instant t2 = t1.plusSeconds(1); // later
        assertEquals(t2, TimeUtils.later(t1, t2));
        assertEquals(t2, TimeUtils.later(t2, t1));
        assertEquals(t1, TimeUtils.later(t1, t1));
        assertEquals(t2, TimeUtils.later(t2, t2));
    }