Win a copy of Think Java: How to Think Like a Computer Scientist this week in the Java in General forum!

# How can i calculate the number of days in year ?

Sudarshan Reddy
Greenhorn
Posts: 20
how can get the number of days in a year ?

ex: i need to calculate the number of days in a year day 2009 ?

Ulf Dittmer
Rancher
Posts: 42967
73
I'm not sure what this has to do with JDBC -which is what this forum is all about- but the question seems to boil down to which year is a leap year, yes? Googling for "isleapyear java source" or something like that should provide you with the code.

Rob Spoor
Sheriff
Posts: 20527
54

Campbell Ritchie
Sheriff
Posts: 48917
58
There are methods in the Calendar classes which can help; they will tell you 1st Feb is the 32nd day of the year.

A lot of people think the Jakarta Commons calendar classes or "Yoda" are better than the standard Java classes.

harilal ithikkat
Ranch Hand
Posts: 221
check whether the year is leap year or not
if( leap year)
366 days
else
365 days

Campbell Ritchie
Sheriff
Posts: 48917
58
It is the GregorianCalendar class which has the method telling you whether it is a leap year.
It is easy enough to work out, which is what I think you are supposed to do:

• Year number divides exactly by 400, OR
• Year number divides exactly by 4 and doesn't divide exactly by 100.
• So 1600, 1904, 1908, 2000, 2004 and 2008 were leap years, but 1900 wasn't.

Vinoth Thirunavukarasu
Ranch Hand
Posts: 164
See this you can Find how its works and create of your own

fred rosenberger
lowercase baba
Bartender
Posts: 12122
30
Campbell Ritchie wrote:It is the GregorianCalendar class which has the method telling you whether it is a leap year.
It is easy enough to work out, which is what I think you are supposed to do:

• Year number divides exactly by 400, OR
• Year number divides exactly by 4 and doesn't divide exactly by 100.
• So 1600, 1904, 1908, 2000, 2004 and 2008 were leap years, but 1900 wasn't.

That will work for modern years, but if you want to go back in history, it gets more complicated. 1752 only had 356 days (or maybe 354 - i'm not sure).

Campbell Ritchie
Sheriff
Posts: 48917
58
It was, I think, 1585 which was 11 days short. But only in Britain; the rest of Europe had changed several years earlier! The date is in the GregorianCalendar documentation as 15th Oct 1582.