Calendar Component to support generic rules like weekends, holidays etc.

Question

Hi all,
I am trying to build a tool which allows me to define various rules for a valid date, e.g.
- only certain days of the week, e.g. monday, tuesday etc.
- date range(s), e.g. 1.JAN.2003-31.MAR.2003, 1.JUL.2003-31.DEC.2003
- blackout range(s), e.g. not between 1.JUL and 5.JUL (independance day in the U.S)
- floating holidays, e.g. easter
etc.
The tool should provide a method
boolean validate(Calendar cal)
which returns true if the passed date is valid, false otherwise.
any suggestions ? are you aware of any commercial or open source products ?
Thanks

Answer 1

look at this:
     * Get weekday for a date. E.g. 21.05.2004 was a friday.
     * @param date Date to inspect.
     * @return One of Calendar.SUNDAY, Calendar.MONDAY, ... or -1 of input date is null.
     * @since 1.6.0
    static public int getWeekday(Date date) {
        int result = -1;
        if (date != null) {
            GregorianCalendar gc = new GregorianCalendar();
            gc.setTime(date);
            result = gc.get(Calendar.DAY_OF_WEEK); //1 = sunday
        }//else: input unavailable
        return result;
    }//getWeekday()
     * Check if date is a weekend (saturday or sunday).
     * @param date Date to check.
     * @return True, if input date is a saturday or sunday.
    static public boolean isWeekend(Date date) {
        boolean result = false;
        if (date != null) {
            int day = getWeekday(date);
            if (day == Calendar.SATURDAY || day == Calendar.SUNDAY) {
                result = true;
        }//else: input unavailable
        return result;
    }//isWeekend()
      * Get easter day in a year (easter sunday).
      * @param year Year to get easter date of.
      * @return Date of easter in <i>year</i>.
     static public Date getEasterDate(int year) {
        Date result = null;
        int a = year % 19;
        int b = year / 100;
        int c = year % 100;
        int d = b / 4;
        int e = b % 4;
        int f = ( b + 8 ) / 25;
        int g = ( b - f + 1 ) / 3;
        int h = ( 19 * a + b - d - g + 15 ) % 30;
        int i = c / 4;
        int k = c % 4;
        int l = (32 + 2 * e + 2 * i - h - k) % 7;
        int m = (a + 11 * h + 22 * l) / 451;
        int p = (h + l - 7 * m + 114) % 31;
        int month = ( h + l - 7 * m + 114 ) / 31;
        int day = p + 1;
        GregorianCalendar gc = new GregorianCalendar(year, month - 1, day);
        result = gc.getTime();
        return result;
    }//getEasterDate()
      * Check if a date is a holiday.
      * @param date Date to check.
     * @param locale Optional locale to check for locale specific holidays.
      * @return True, if <i>date</i> is a holiday.
     * @see <a href="http://www.loisl.de/kalender/Berechnung.htm">Kalenderberechnung</a>
     static public boolean isHoliday(Date date, Locale locale) {
        boolean result = false;
        if (date != null) {
            date = setTime(date, null); //set time to 00:00:00
            GregorianCalendar gc = new GregorianCalendar();
            gc.setTime(date);
            int day = gc.get(Calendar.DAY_OF_MONTH); //first day = 1
            int month = gc.get(Calendar.MONTH); //first month = 0
            int year = gc.get(Calendar.YEAR);
            //******* variable holidays for all locales: *******
            //easter:
            GregorianCalendar easter = new GregorianCalendar();
            easter.setTime(setTime(getEasterDate(year), null)); //set time to 00:00:00
            //******* locale specific holidays: *******
            if (locale == null) {
                locale = Locale.getDefault();
            if (locale.getCountry().equals(Locale.GERMANY.getCountry())) {
                if (day == 1 && month == Calendar.JANUARY) { //Neujahr
                    result = true;
                } else if (day == 1 && month == Calendar.MAY) { //Maifeiertag (Tag der Arbeit)
                    result = true;
                } else if (day == 3 && month == Calendar.OCTOBER) { //Tag der deutschen Einheit
                    result = true;
//                    } else if (day == 31 && month == Calendar.OCTOBER) { //Reformationstag (nicht in allen Bundesl�ndern)
//                        result = true;
//                    } else if (day == 1 && month == Calendar.NOVEMBER) { //Allerheiligen (nicht in allen Bundesl�ndern)
//                        result = true;
                } else if (day == 25 && month == Calendar.DECEMBER) { //1. Weihnachtstag
                    result = true;
                } else if (day == 26 && month == Calendar.DECEMBER) { //2. Weihnachtstag
                    result = true;
//                  easter.add(Calendar.DAY_OF_YEAR, -46);
//                  if (date.equals(easter.getTime())) { //Aschermittwoch
//                      result = true;
//                  easter.add(Calendar.DAY_OF_YEAR, 46);
//                  easter.add(Calendar.DAY_OF_YEAR, -3);
//                  if (date.equals(easter.getTime())) { //Gr�ndonnerstag
//                      result = true;
//                  easter.add(Calendar.DAY_OF_YEAR, 3);
                easter.add(Calendar.DAY_OF_YEAR, -2);
                if (date.equals(easter.getTime())) { //Karfreitag
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, 2);
                if (date.equals(easter.getTime())) { //Ostersonntag?
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, 1);
                if (date.equals(easter.getTime())) { //Ostermontag
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, -1);
                easter.add(Calendar.DAY_OF_YEAR, 39);
                if (date.equals(easter.getTime())) { //Christi Himmelfahrt
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, -39);
                easter.add(Calendar.DAY_OF_YEAR, 49);
                if (date.equals(easter.getTime())) { //Pfingstsonntag
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, -49);
                easter.add(Calendar.DAY_OF_YEAR, 50);
                if (date.equals(easter.getTime())) { //Pfingstmontag
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, -50);
                easter.add(Calendar.DAY_OF_YEAR, 60);
                if (date.equals(easter.getTime())) { //Fronleichnam
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, -60);
            } else if (locale.getCountry().equals(Locale.FRANCE.getCountry())) {
                if (day == 15 && month == Calendar.AUGUST) { //Assomption
                    result = true;
                } else if (day == 1 && month == Calendar.NOVEMBER) { //Toussaint
                    result = true;
                } else if (day == 11 && month == Calendar.NOVEMBER) { //F�te de l'Armistice 1918
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, 39);
                if (date.equals(easter.getTime())) { //Ascension
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, -39);
                easter.add(Calendar.DAY_OF_YEAR, 49);
                if (date.equals(easter.getTime())) { //Pentec�te
                    result = true;
                easter.add(Calendar.DAY_OF_YEAR, -49);
            } else if (locale.getCountry().equals(Locale.US.getCountry())) { //USA?
                if (day == 4 && month == Calendar.JULY) { //Independence Day
                    result = true;
                } else if (day == 6 && month == Calendar.SEPTEMBER) { //Labour Day
                    result = true;
                } else if (day == 11 && month == Calendar.OCTOBER) { //Columbus Day
                    result = true;
                } else if (day == 11 && month == Calendar.NOVEMBER) { //Veterans' Day
                    result = true;
            } else if (locale.getCountry().equals(Locale.JAPAN.getCountry())) {
                if (day == 23 && month == Calendar.SEPTEMBER) { //Autumnal Equinox Day
                    result = true;
                } else if (day == 11 && month == Calendar.OCTOBER) { //Health-Sports Day
                    result = true;
                } else if (day == 3 && month == Calendar.NOVEMBER) { //Culture Day
                    result = true;
            }//else: unknown locale
        }//else: input unavailable
        return result;
    }//isHoliday()