Collectors update

Kevin Bourrillion kevinb at
Tue Feb 5 12:20:33 PST 2013

On Tue, Feb 5, 2013 at 11:11 AM, Remi Forax <forax at> wrote:

 4.  Rejigger Partition to return an array again, with an explicit
>>>> lambda (which will likely be an array ctor ref) to make the array.
>>>> Eliminated the silly Partition class.
>>> Please don't do that, it's pure evil.
>>>    public static<T> Collector<T, Collection<T>[]>
>>> partitioningBy(Predicate<T> predicate, IntFunction<Collection<T>[]>
>>> arraySupplier) {
>> I've refactored this to make the partition collectors return Map<Boolean,
>> X>.
> I think returning a boolean -> T (or Boolean -> T) is better because it's
> conceptually more lightweight than a Map.
> I expect to see more function instead of a Map returned as result of a
> method.

I'd have to disagree; I expect function objects to be little things I pass *
in*, but I think it's more intuitive to expect a proper data structure back

Kevin Bourrillion | Java Librarian | Google, Inc. | kevinb at

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