These automaton intersection APIs are frustrating with all the special case handling... Ideas welcome!
We've had similar challenges with them in the past, when a user invoked Terms.intersect directly instead of via CompiledAutomaton: https://issues.apache.org/jira/browse/LUCENE-7576 The problem is CompiledAutomaton specializes certain cases (all strings match, no strings match, single term) and sidesteps Terms.intersect for those cases. We should fix AutomatonTermsEnum public ctor w/ the same checks (insist on a NORMAL case) so you don't hit assert failures, or, worse ... I'll do that. I think a new CompiledAutomaton.intersect taking TermsEnum would be tricky in general because it relies on the (efficient) Terms.intersect to handle the NORMAL case well, but we can't invoke that from a TermsEnum. In the SINGLE case, could you use SingleTermsEnum, passing the TermsEnum from your doc values, and the term from the CompiledAutomaton? Would that suffice as a workaround? Mike McCandless http://blog.mikemccandless.com On Fri, Jan 6, 2017 at 11:17 AM, Alan Woodward <a...@flax.co.uk> wrote: > We’ve hit an issue while developing marple, where we want to have the > ability to filter the values from a SortedDocValues terms dictionary. > Normally you’d create a CompiledAutomaton from the filter string, and then > call #getTermsEnum(Terms) on it; but for docvalues, we don’t have a Terms > instance, we instead have a TermsEnum. > > Using AutomatonTermsEnum to wrap the TermsEnum works in most cases here, but > if the CompiledAutomaton in question is a fixed string, then we get > assertion failures, because ATE uses the compiled automaton’s internal > ByteRunAutomaton for filtering, and fixed-string automata don’t have one. > > Is there a work-around that I’m missing here? Or should I maybe open a JIRA > to add a #getTermsEnum(TermsEnum) method to CompiledAutomaton? > > Alan Woodward > www.flax.co.uk > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
