public void test_isAfter(int hour1, int minute1, ZoneId zone1, int hour2, int minute2, ZoneId zone2, boolean expected) {

    ZonedDateTime a = ZonedDateTime.of(LocalDateTime.of(2008, 6, 30, hour1, minute1), zone1);
    ZonedDateTime b = ZonedDateTime.of(LocalDateTime.of(2008, 6, 30, hour2, minute2), zone2);
    assertEquals(a.isAfter(b), expected);
    assertEquals(b.isAfter(a), false);
    assertEquals(a.isAfter(a), false);
    assertEquals(b.isAfter(b), false);
  }

  @Test(expectedExceptions = NullPointerException.class, groups = { "tck" }