[LUCENE-10045] Extend ConjunctionUtils to support LongValues and DoubleValues

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Won't Fix
• Affects Version/s: 9.0
• Component/s: core/search
• Lucene Fields: New
• Assignee: Greg Miller
• Reporter: Greg Miller
• Created: 05/Aug/21 16:11
• Updated: 28/Aug/22 16:24
• Resolved: 17/Aug/21 16:14

Description

ConjunctionUtils provides nice support for wrapping a list of DISIs or Scorers into one DISI for easy conjunctive iteration, but intersecting DISIs/Scorers with LongValues or DoubleValues remains more burdensome. We have this pattern in a few different places (particularly in faceting code, but I suspect it exists elsewhere as well):

LongValues fv = [...];
DocIdSetIterator docs = [...];
for (int doc = docs.nextDoc(); doc != DocIdSetIterator.NO_MORE_DOCS; ) {
  if (fv.advanceExact(doc)) {
    // do something
  }
  doc = docs.nextDoc();
}

It would be nice to encapsulate this logic in a common implementation, accessible through ConjunctionUtils. Note that this works great for things like NumericDocValues since they implement DISI and can be wrapped, but LongValues/DoubleValues don't implement DISI (and can't lead iteration), so we would need a separate implementation that explicitly takes a "lead" iterator and then a collection of LongValues/DoubleValues to intersect.

Issue Links

• links to: GitHub Pull Request #233