public static Instant toJoda(java.time.Instant instant) {
    return Optional.ofNullable(instant).map(t -> new Instant(t.toEpochMilli())).orElse(null);
  }
@Test
  public void shouldConvertToJodaInstant() {
    assertThat(TimeUtil.toJoda(null)).isNull();
    assertThat(TimeUtil.toJoda(java.time.Instant.ofEpochMilli(0L)))
        .isEqualTo(org.joda.time.Instant.ofEpochMilli(0L));
  }