Finding days difference in java

Question

After consulting a few forums, I ended up using the code below to find the days difference. But, I see a problem with the logic (may be it\'s my over sight?). I see that for

Answer 1

1000 * 60 * 60 * 24 is wrong way to find day difference. You can use JodaTime but there is a pure java solution.

Let we have two inialized variables

Calendar firstDay = ...;
Calendar secondDay = ...;

and

firstDay.before(lastDay)

is true.

Run

int firstDayNo = firstDay.get(Calendar.DAY_OF_YEAR);
int secondDayNo = secondDay.get(Calendar.DAY_OF_YEAR);
int dayDifference, yearMultiplier;

dayDifference = -firstDayNo;
yearMultiplier = secondDay.get(Calendar.YEAR) - firstDay.get(Calendar.YEAR);
while (yearMultiplier > 0) {
    dayDifference += firstDay.getActualMaximum(Calendar.DAY_OF_YEAR);
    firstDay.add(Calendar.YEAR, 1);
    yearMultiplier--;
}
dayDifference += secondDayNo;

return dayDifference;