Hello! Thanks for review! Here's the updated patch: http://cr.openjdk.java.net/~tvaleev/webrev/8146218/r2/
SC> The docs say that if the end date is before the start date, the SC> stream is empty. While I can see just about why LongStream.range() SC> works that way, I don't think this API should. The minimum is an SC> exception, but it would be easy to support negative in the SC> days-only case or the months-only case. The problem is where there SC> are both months/years and days and those should be exceptions. Now datesUntil(endExclusive) throws an IllegalArgumentException if end date is before start date. datesUntil(endExclusive, step) supports negative periods. It throws IllegalArgumentException if: - step is zero - step.toTotalMonths() and step.getDays() both non-zero and have opposite sign - step is negative and end date is after start date - step is positive and end date is before start date Otherwise it works correctly: you can use LocalDate.of(2016, 1, 1) .datesUntil(LocalDate.of(2015, 1, 1), Period.ofMonths(-1)); Steps like Period.of(-1, -1, -1) are also supported. SC> The single-arg implementation uses plusDays() with an SC> incrementing number. When the performance patch goes in, the SC> proposed streaming implementation will be optimal for small SC> streams but less optimal for large ones. The fastest way to loop SC> over a list of dates would be to manually generate them by SC> incrementing the day until it exceeds the length of month, and so SC> on. However, this would be serial. As I understand, plusDays performance patch is already pushed. It's possible to write custom Spliterator which would use previous.plusDays(1) in tryAdvance() and jump (via LocalDate.of(startEpochDay+n)) in trySplit() if parallel processing is requested. However this adds at least one additional class and more complexity. I guess, such optimization can be considered later as separate issue when API is stabilized. SC> As such, I think the best way to write this, taking account of SC> how plusDays() is implemented, is as follows: SC> LongStream.range(start.toEpochDay(), SC> end.toEpochDay()).mapToObj(LocalDate::ofEpochDay); Ok, now it's done this way. SC> In the period-based method, it would be best to capture the case SC> where totalMonths == 0 and days > 0 and forward to another method SC> that ignores months. That private method can share implementation SC> with the public single-arg method (passing in 1). This case still more complex than one-day case as it requires division and multiplication. Thus I'd keep these case separately. However I simplified "months = 0" path using ofEpochDay, now it should be faster. SC> The docs for the period-based method should specify the strategy SC> that produces the results (in abstract terms). This needs to cover SC> that the result is equivalent to always adding to the start period SC> a multiple of the period. I added some clarifications, please check. SC> Some nits: SC> I prefer to avoid @link in the first sentence. Just using 'stream' would be sufficient. Done. SC> The first sentence should be a summary. In this case it probably has a bit too much detail. Done. SC> The @return has 'values' on a new line when it could be on the same line. I set now line length = 100 characters in my IDE. Is it ok? SC> If statements need braces. Done. With best regards, Tagir Valeev.