Re: Calendar: month problem..
EricF wrote:
In article <76ydnZiyTvCNNNTbnZ2dnUVZ_r-onZ2d@comcast.com>, Lew <lew@nospam.lewscanon.com> wrote:
Ian Wilson wrote:
Roedy Green wrote:
On Wed, 09 May 2007 14:32:57 -0400, maya <maya778899@yahoo.com>
wrote, quoted or indirectly quoted someone who said :
why June? when Month chosen is 5?
This is one of many calendar and date gotchas . Sun numbers months
starting at 0 instead of 1 like everyone else.
Not everyone else, Perl does too.
And Java array indices start at 0. Computer science is full of zero-based
concepts. It is what it is and that's why Sun publishes their Javadocs for
all to see.
I can't disagree but it's pretty lame. Month 1 in the real world is Jan. The
Java domain model for dates/time is just a mess. JSR310 should clean it up.
Date and time are 2 separate (though related) concepts. If I create a Date
object at 10:00 am and at 11:00 am on the same day, I'd expect them to be
equal. Wrong.
Ultimately, this is all a consequence of what I consider to be a basic
error in Java array design, the forced zero start.
If Java had allowed specification of a start index as well as a number
of elements for each array, Calendar could have used the month number,
rather than a zero-based month index, and still have been able to use it
as an array index.
In addition to the choice between 0 and 1 there are some cases where it
makes sense to have, for example, elements -1, 0, and 1.
Mapping from the most natural start index for a particular array to zero
based has to be done. The choice is between it being done by the
programmer, or by the programming language. Leaving it to the programmer
results in less natural code, and creates temptations to have things
start at zero whether or not it makes any sense.
Patricia