Why does Calendar.get(Calendar.MONTH) return 0?

Question

why does the following return 0?

int currMonth = c.get(Calendar.MONTH);

@Mark E: [Calendar](http://download.oracle.com/javase/6/docs/api/java/util/Calendar.html) — Sean Patrick Floyd, Jan 14 '11 at 18:12

score 55 · Accepted Answer · answered Jan 14 '11 at 18:12

55

The Months are numbered from 0 (January) to 11 (December).

Reference:

answered Jan 14 '11 at 18:12

4

The last depends on the number of months in the year.... – Mark Byers Jan 14 '11 at 18:17
@Byers: And whether "0" means "January" or "Abib" or "Zhengyue" depends on what calendar you are using. But I think it's a fair assumption that he's talking about the Gregorian calendar. Which last I checked has had 12 months in a year since it was invented in 1582. I'm all for keeping systems flexible, but on the list of things likely to change, the number of months in a calendar year is pretty far down. – Jay Jan 14 '11 at 18:25
2

FWIW, Java supports Undecimber, a thirteenth month of the year used in lunar calendars... – Brian Knoblauch Jan 17 '11 at 14:18
@Brian where can I find that? – Sean Patrick Floyd Jan 17 '11 at 14:22
@Sean http://download.oracle.com/javase/6/docs/api/java/util/Calendar.html – Brian Knoblauch Jan 17 '11 at 14:32
@Brian arghh, I was blind. sorry. – Sean Patrick Floyd Jan 17 '11 at 14:42

score 12 · Answer 2 · answered Jan 14 '11 at 18:13

12

Not natural indexing, but unnatural thinking of Sun people. :-)

answered Jan 14 '11 at 18:13

Axel Fontaine

1

I'm wondering: should I upvote this or flag as offensive? I'll go for neither – Sean Patrick Floyd Jan 14 '11 at 18:15
No, I don't think so. Why should January be represented **numerically** as 1 (I'm not talking about textually)? Sure the String representation can be 1 in many the way many cultures write out dates, but that's handled by date formatters, not Calendar. 1+ rep for the smiley though. – Hovercraft Full Of Eels Jan 14 '11 at 18:15
1

Maybe it's just me, but I find mapping 1 (numeric) to 1 (text) just a wee bit easier... :-) – Axel Fontaine Jan 14 '11 at 18:20
I think that its definitely right to start it from 0 to conform with other indexing methods in Java. It was a dumb question on my behalf really - sorry to waste expert time! – dr85 Jan 14 '11 at 18:41
1

@David, it is not a dumb question, as the semantics are very confusing. I do however disagree with you. 0 really is the source of a lot of confusion. – Axel Fontaine Jan 14 '11 at 18:47

score 0 · Answer 3 · answered Jan 14 '11 at 18:09

0

oops! sorry - I figured it out. Natural Indexing of course!!!

answered Jan 14 '11 at 18:09

dr85

You don't use numbers for months but should use the Calendar constants such as Calendar.JANUARY (which as you're finding out is 0). The API shows this. – Hovercraft Full Of Eels Jan 14 '11 at 18:10
3

Calendar constants don't make any sense if you're trying to get the month number. In that case one must just remember to increment the return value. I find it quite annoying, especially since days are returned starting with 1... – Brian Knoblauch Jan 14 '11 at 18:15
yeah that is a bit stranfe... – dr85 Jan 14 '11 at 18:43

3 Answers3