Check if the Calendar date is a sunday

Question

I am trying to figure out how to make my program count the number of Sundays in a week.

I have tried the following thing:

if (date.DAY_OF_WEEK == date.SU         


        

Answer 1

Calendar cal = ...;
if (cal.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {
    System.out.println("Sunday!");
}

Calendar.DAY_OF_WEEK always equals to 7 no matter what instance of Calendar you are using (see this link), it is a constant created to be used with the Calendar.get() method to retrieve the correct value.

It is the call to Calendar.get(Calendar.DAY_OF_WEEK) that will return the real day of week. Besides, you will find useful values in the Calendar class like Calendar.SUNDAY (and the other days and months) in order for you to be more explicit in your code and avoid errors like JANUARY being equal to 0.

Edit

Like I said, the Calendar class does contains useful constants for you to use. There is no month number 12 they start at 0 (see above), so DECEMBER is month number 11 in the Java Date handling.

Calendar startDate = Calendar.getInstance();
startDate.set(2012, Calendar.DECEMBER, 02);
if (startDate.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {
    System.out.println("true");
} else {
    System.out.println("FALSE");
}

Will print true of course.