Jave获取当前日期的上一个月最后一天或者下一个月最后一天

	public final static Date addMonths(final Date date, final Integer noOfMonths) {
		Calendar orgCal = GregorianCalendar.getInstance();
		orgCal.setTime(date);
		Calendar newCal = GregorianCalendar.getInstance();
		newCal.setTime(date);
		newCal.set(Calendar.DAY_OF_MONTH, 1);
		int year = orgCal.get(Calendar.YEAR);
		int month = orgCal.get(Calendar.MONTH) + 1;

		// Calculate no. of month and no. of year should be added
		int years_to_add = noOfMonths / 12;
		int months_to_add = noOfMonths - 12 * years_to_add;
		year += years_to_add;
		month += months_to_add;
		if (month > 12) {
			month -= 12;
			year++;
		} else if (month < 1) {
			month += 12;
			year--;
		}
		// Set the year and month
		newCal.set(Calendar.YEAR, year);
		newCal.set(Calendar.MONTH, month - 1);
		// The input date is last date of month
		if (date.equals(lastDate(date))) {
			newCal.set(Calendar.DAY_OF_MONTH, newCal
					.getActualMaximum(Calendar.DAY_OF_MONTH));
		} else if (newCal.getActualMaximum(Calendar.DAY_OF_MONTH) < orgCal
				.get(Calendar.DAY_OF_MONTH))
			newCal.set(Calendar.DAY_OF_MONTH, newCal
					.getActualMaximum(Calendar.DAY_OF_MONTH));
		else
			newCal
					.set(Calendar.DAY_OF_MONTH, orgCal
							.get(Calendar.DAY_OF_MONTH));
		Date result = newCal.getTime();
		orgCal = null;
		newCal = null;
		return result;
	}