Converting Date to LocalTime can rely on the LocalTime.toInstant() method as follows:

// e.g., 08:03:20.336
public static LocalTime dateToLocalTime(Date date) {

  return LocalTime.ofInstant(dateToInstant(date), DEFAULT_TIME_ZONE);
}

Converting LocalTime to Date should take into account that LocalTime doesn't have a date component. This means that the solution should set the date on January 1, 1970, the epoch:

// e.g., Thu Jan 01 08:03:20 EET 1970
public static Date localTimeToDate(LocalTime localTime) {

  return Date.from(localTime.atDate(LocalDate.EPOCH)
    .toInstant(DEFAULT_TIME_ZONE.getRules()
      .getOffset(Instant.now())));
}