IntStream.sum

[Remi Forax]

On 01/16/2013 02:14 PM, Joe Bowbeer wrote:
>
> Normally I would side with the stricter argument in order to avoid 
> potential harm, but in this case I don't see the problem.
>

the problem is that id doesn't solve the overflow problem, it just hide 
it more.

> Code quality tools will flag the (int), right?
>

yes, raising the number of false positive warnings.

> And long can hold the result of MAXINT additions?
>

stream are sized is store in a long if a size if definite or can be infinite
so it solves nothing.

Rémi

> On Jan 16, 2013 4:01 AM, "Remi Forax" <forax at univ-mlv.fr 
> <mailto:forax at univ-mlv.fr>> wrote:
>
>     IntStream.sum have just been changed to return a long instead of
>     an int and I don't think it's a good idea.
>
>     There is 3 ways to deal with overflows:
>       1) do nothing, the Java default semantics
>       2) throw an exception if overflown (using Integer.addExact by
>     example)
>       3) use BigInteger
>     all other ways are just half baked solution.
>
>     This one is very bad because usually users will use it that way,
>       int sum = (int)intStream.sum();
>     so it doesn't solve anything, just make the semantics awkward.
>
>     sum() is just a shortcut for a reduce, so it should stick with the
>     default Java semantics,
>     if users want longs, they can use reduce with Long::add or
>     Long::addExact.
>
>     Rémi
>
>
>
>
>