@Override
  public int compare(ChronoZonedDateTime<?> date1, ChronoZonedDateTime<?> date2) {
    return ChronoZonedDateTime.timeLineOrder().compare(date1, date2);
  }
@Test
  void should_disregard_chronology_difference() {
    ZonedDateTime now = ZonedDateTime.now();
    ZonedDateTime inTokyo = now.withZoneSameInstant(ZoneId.of("Asia/Tokyo"));
    ChronoZonedDateTime<JapaneseDate> inTokyoJapanese = JapaneseChronology.INSTANCE.zonedDateTime(now);

    assertThat(inTokyoJapanese.compareTo(inTokyo)).as("Built-in comparison should report that they differ").isNotZero();
    assertThat(comparator.compare(inTokyoJapanese, inTokyo)).isZero();
  }