Analog of ORACLE function MONTHS_BETWEEN in Java

Question

Does Java have some analog of Oracle\'s function MONTHS_BETWEEN?

Answer 1

Actually, I think the correct implementation is this one:

public static BigDecimal monthsBetween(final Date start, final Date end, final ZoneId zone, final int scale ) {
    final BigDecimal no31 = new BigDecimal(31);

    final LocalDate ldStart = start.toInstant().atZone(zone).toLocalDate();
    final LocalDate ldEnd = end.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();

    final int endDay = ldEnd.getDayOfMonth();
    final int endMonth = ldEnd.getMonthValue();
    final int endYear = ldEnd.getYear();
    final int lastDayOfEndMonth = ldEnd.lengthOfMonth();

    final int startDay = ldStart.getDayOfMonth();
    final int startMonth = ldStart.getMonthValue();
    final int startYear = ldStart.getYear();
    final int lastDayOfStartMonth = ldStart.lengthOfMonth();

    final BigDecimal diffInMonths = new BigDecimal((endYear - startYear)*12+(endMonth-startMonth));
    final BigDecimal fraction;
    if(endDay==startDay || (endDay==lastDayOfEndMonth && startDay==lastDayOfStartMonth)) {
        fraction = BigDecimal.ZERO;
    }
    else {
        fraction = BigDecimal.valueOf(endDay-startDay).divide(no31, scale, BigDecimal.ROUND_HALF_UP);
    }
    return diffInMonths.add(fraction);
}

public static BigDecimal monthsBetween(final Date start, final Date end) {
    return monthsBetween(start, end, ZoneId.systemDefault(), 20);
}