On Sun, 7 Nov 2021 03:53:29 GMT, Michael Bien <d...@openjdk.java.net> wrote:
>> src/java.base/share/classes/java/util/Collection.java line 743:
>>
>>> 741: */
>>> 742: default Stream<E> stream() {
>>> 743: if (isEmpty()) return Stream.empty();
>>
>> The net effect of this change might depend on your workload. If you call
>> stream() on empty collections that have cheap isEmpty(), this change will
>> likely improve performance and reduce waste. However, this same change might
>> do the opposite if some of your collections aren't empty or have costly
>> isEmpty(). It would be good to have benchmarks for different workloads.
>
> wouldn't this make streams no longer lazy if the collection is empty?
>
> List<String> list = new ArrayList<>();
> Stream<String> stream = list.stream();
>
> list.addAll(List.of("one", "two", "three"));
>
> stream.forEach(System.out::println); // prints one two three
(immutable collections could override stream() instead, since they don't have
that problem)
-------------
PR: https://git.openjdk.java.net/jdk/pull/6275
