On Thu, 9 Nov 2023 09:39:33 GMT, Tagir F. Valeev <tval...@openjdk.org> wrote:
>> Ah, now I see what you mean. In this specific case you might be able to >> create a combiner (which would also need a Downstream) such that you can add >> the missing combinations (the end of the "left" and the beginning of the >> "right"). But imagine something like `windowFixed(3)`, where the presence of >> 1 or 2 elements to the "left" will skew all the elements to the "right", >> potentially rippling through the entire stream. >> >> I think the Preview is a perfect place to see if the combiner would be made >> even better with a Downstream reference or not. Logically, the output of >> said Downstream would be placed *after* the "left"'s output, and *before* >> the "right"'s output (so in the middle of the two). >> >> But then someone might want to be able to inject elements outside of that >> order, but I guess that remains to be seen. >> >> Great thoughts, @amaembo 👍 > > With windowFixed, true parallelization is not possible, unless the stream is > SIZED/SUBSIZED, but this information is not available for Gatherer, so we > cannot solve this at all (and this is probably a reasonable limitation of the > API). > >> But then someone might want to be able to inject elements outside of that >> order, but I guess that remains to be seen. > > Not sure where one may want to inject other elements. If you want to add > something after the right output, you can do this inside the finisher, or the > next combiner, when the "right" will become the "left". There are no other > places to insert. E.g., you cannot insert "before left", because downstream > collector has no corresponding operation. To me it looks like inserting after > the "left" part is the only possibility. @amaembo Alright, then I think we are aligned. Experimentation with combiner-downstream should be possible during the Preview-cycle ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/16420#discussion_r1387776261
