On Fri, Oct 4, 2024 at 1:30 PM Alex Herbert <alex.d.herb...@gmail.com> wrote:
> You cannot return an empty BloomFilter when there is no array of > BloomFilters to flatten. The BloomFilter is tied to a Shape. Without a > shape you cannot know what size filter to create. So we have to return > null or throw an exception. Whatever choice must be documented. > The code now throws an exception instead of returning null. I also updated the Javadoc. > > Note we do not currently check if the Shapes are all equal when > creating the BloomFilterExtractor. This is not essential but when > merging two Bloom filters in flatten an error will be thrown if the > filters are not compatible. I say it is not essential as the > functionality of the BloomFilterExtract in processBloomFilters does > not mandate any prerequisites on the Predicate for the filters. So for > example you could have many filters of different sizes and a predicate > that tests if they all contain a given IndexProducer. > I'll leave that deeper topic alone for now, and for you and Claude to further discuss if warranted. TY, Gary > > Alex > > On Fri, 4 Oct 2024 at 18:02, Gary Gregory <garydgreg...@gmail.com> wrote: > > > > OK, but how do you create an empty filter? > > > > Gary > > > > On Fri, Oct 4, 2024, 12:54 PM Claude Warren <cla...@xenei.com> wrote: > > > > > I think that it should return an empty filter as the javadoc says > > > > > > > > > On Fri 4 Oct 2024, 15:53 Gary D. Gregory, <ggreg...@apache.org> wrote: > > > > > > > See the new disabled test BloomFilterExtractorTest. > > > > > > > > Gary > > > > > > > > On 2024/10/04 14:51:55 "Gary D. Gregory" wrote: > > > > > Hi Claude and all, > > > > > > > > > > The method: > > > > > > > > > > > > > > > > > > org.apache.commons.collections4.bloomfilter.BloomFilterExtractor.flatten() > > > > > > > > > > is documented as always returning a BloomFilter: > > > > > > > > > > /** > > > > > * Create a standard (non-layered) Bloom filter by merging all > of > > > > the layers. If > > > > > * the filter is empty this method will return an empty Bloom > > > filter. > > > > > * > > > > > * @return the merged bloom filter. > > > > > */ > > > > > > > > > > But that's not how it's coded, it can return null, the simplest > > > > reproducer is: > > > > > > > > > > BloomFilterExtractor.fromBloomFilterArray(new > BloomFilter[0]).flatten() > > > > -> null > > > > > > > > > > Should we: > > > > > > > > > > - Change the Javadoc > > > > > - Change the code > > > > > -- How should this code be changed? > > > > > -- Should the method be moved to BloomFilter and use "this" as the > > > > default filter? > > > > > > > > > > TY, > > > > > Gary > > > > > > > > > > > --------------------------------------------------------------------- > > > > > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > > > > > For additional commands, e-mail: dev-h...@commons.apache.org > > > > > > > > > > > > > > > > > > --------------------------------------------------------------------- > > > > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > > > > For additional commands, e-mail: dev-h...@commons.apache.org > > > > > > > > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > >
