On Thu, 13 Nov 2025 06:46:51 GMT, Patrick Strawderman <[email protected]> wrote:
>> When `Comparator.naturalOrder()` was explicitly supplied to a collection >> such as `TreeSet`, or passed into the `sorted` method of a stream, the >> sorted characteristic was not preserved, causing unnecessary buffering and >> duplicate sorting. >> >> Example: >> >> >> TreeSet<Integer> sortedSet = new TreeSet<>(Comparator.naturalOrder()); >> sortedSet.add(1); >> sortedSet.add(2); >> // SortedOps.OfRef.opWrapSink is not a no-op >> sortedSet.stream().sorted().forEach(System.out::println); >> >> or >> >> TreeSet<Integer> sortedSet = new TreeSet<>(); >> sortedSet.add(1); >> sortedSet.add(2); >> // SortedOps.OfRef.opWrapSink is not a no-op >> sortedSet.stream().sorted(Comparator.naturalOrder()).forEach(System.out::println); >> >> >> This PR updates `SortedOps.makeRef` and `StreamOpFlag.fromCharacteristics` >> to handle the above cases and avoid the unnecessary sort step. > > Patrick Strawderman has updated the pull request incrementally with one > additional commit since the last revision: > > Fix StreamOpFlagsTest I don't know about the particular case about TreeSet, but I think with the advent of Comparator.naturalOrder in Java 8, people are much more likely to use it instead of null to represent the natural order, especially for Comparator-returning methods or Comparator fields. Offering such a conversion within the implementation, in my opinion, is better than checking and converting at every single use site that has a Comparator. ------------- PR Comment: https://git.openjdk.org/jdk/pull/28226#issuecomment-3535108496
