paul.sandoz at oracle.com
Wed Jun 5 09:50:45 PDT 2013
On Jun 5, 2013, at 6:31 PM, Michael Nascimento <misterm at gmail.com> wrote:
> Hi folks,
> Is there any good reason I cannot see for Collectors.sumBy, giving one
> could use mapToLong().sum() and avoid the costs of boxing?
Such Collector can be used with mapping, groupingBy and partitioningBy, e.g.
Stream<Foo> s = ...
Map<Foo, Long> m = s.collect(groupingBy(Function::identity, sumBy(this::mapFooToLong)));
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