Calculate number of weekdays between two dates in Java

public static int getWorkingDaysBetweenTwoDates(Date startDate, Date endDate) {
    Calendar startCal = Calendar.getInstance();
    startCal.setTime(startDate);        

    Calendar endCal = Calendar.getInstance();
    endCal.setTime(endDate);

    int workDays = 0;

    //Return 0 if start and end are the same
    if (startCal.getTimeInMillis() == endCal.getTimeInMillis()) {
        return 0;
    }

    if (startCal.getTimeInMillis() > endCal.getTimeInMillis()) {
        startCal.setTime(endDate);
        endCal.setTime(startDate);
    }

    do {
       //excluding start date
        startCal.add(Calendar.DAY_OF_MONTH, 1);
        if (startCal.get(Calendar.DAY_OF_WEEK) != Calendar.SATURDAY && startCal.get(Calendar.DAY_OF_WEEK) != Calendar.SUNDAY) {
            ++workDays;
        }
    } while (startCal.getTimeInMillis() < endCal.getTimeInMillis()); //excluding end date

    return workDays;
}

Start date and end date are exclusive, Only the days between given dates will be counted. Start date and end date will not be included.

Solution without loop:

static long days(Date start, Date end){
    //Ignore argument check

    Calendar c1 = Calendar.getInstance();
    c1.setTime(start);
    int w1 = c1.get(Calendar.DAY_OF_WEEK);
    c1.add(Calendar.DAY_OF_WEEK, -w1);

    Calendar c2 = Calendar.getInstance();
    c2.setTime(end);
    int w2 = c2.get(Calendar.DAY_OF_WEEK);
    c2.add(Calendar.DAY_OF_WEEK, -w2);

    //end Saturday to start Saturday 
    long days = (c2.getTimeInMillis()-c1.getTimeInMillis())/(1000*60*60*24);
    long daysWithoutWeekendDays = days-(days*2/7);

    // Adjust days to add on (w2) and days to subtract (w1) so that Saturday
    // and Sunday are not included
    if (w1 == Calendar.SUNDAY && w2 != Calendar.SATURDAY) {
        w1 = Calendar.MONDAY;
    } else if (w1 == Calendar.SATURDAY && w2 != Calendar.SUNDAY) {
        w1 = Calendar.FRIDAY;
    } 

    if (w2 == Calendar.SUNDAY) {
        w2 = Calendar.MONDAY;
    } else if (w2 == Calendar.SATURDAY) {
        w2 = Calendar.FRIDAY;
    }

    return daysWithoutWeekendDays-w1+w2;
}