Finding the difference in days between two dates

[JakeD]

Im writing a metro card program and I want to output how many days a person has left on their card by subtracting the date current date from the expiration date they imputed. However im unsure how to do this. Ive looked at the Date class and the Gregorian calender class. However, java wont allow me to subtract one Gregorian date from another. The same is true for the date class.

What class should I use or what should I do differently to obtain the difference in days between two dates?

[mwa103]

I found this site which talks about how to use the Calendar to find such things as the date 30 days from today. Not sure if this will be helpful or not though since you said you already tried the Calendar class.

-Mike

http://www.unix.org.ua/orelly/java-ent/jnut/ch04_04.htm

[JakeD]

Thanks for the response, Ill try the site now.

[ram_2k]

Hi,

you can use java.util.Date compareTo(), it will return whether the given Date is less or greater than the current Date object.

If you want to get the no. of days difference, you have to do it manually by getDate(), getMonth for both the dates and compare it.

To my best knowledge, i dont think there is a method which provides the difference in dates.

[JakeD]

Hey, thanks for the help guys. I actually learned how. You have to get the dates, set the hours minutes and seconds to zero using

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Calendar.set(MINUTES, 00)

etc. and then convert them to gregorian calenders using

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GregorianCalendar.setTime(date).

Then you convert both your greograin calendar objects to milliseconds using

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Gregorian.getTimeMillis()

and then you subtract them from there.