@Override
  public int compare(ChronoLocalDateTime<?> date1, ChronoLocalDateTime<?> date2) {
    return ChronoLocalDateTime.timeLineOrder().compare(date1, date2);
  }
@Test
  void should_disregard_chronology_difference() {
    // GIVEN
    LocalDateTime now = LocalDateTime.now();
    JapaneseDate japaneseDate = JapaneseDate.from(now);
    ChronoLocalDateTime<JapaneseDate> nowInJapanese = japaneseDate.atTime(now.toLocalTime());
    // THEN
    assertThat(now.compareTo(nowInJapanese)).as("Built-in comparison should report that they differ").isNotZero();
    assertThat(comparator.compare(now, nowInJapanese)).isZero();
    assertThat(comparator.compare(now, now)).isZero();
  }