Package org.apache.lucene.search

Class ImpactsDISI

  • public final class ImpactsDISI
extends DocIdSetIterator
    DocIdSetIterator that skips non-competitive docs thanks to the indexed impacts. Call setMinCompetitiveScore(float) in order to give this iterator the ability to skip low-scoring documents.
    NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

    • Constructor Detail

      • ImpactsDISI

        public ImpactsDISI​(DocIdSetIterator in,
                   MaxScoreCache maxScoreCache)
        Sole constructor.
        Parameters:
        in - the iterator, typically an ImpactsEnum
        maxScoreCache - the cache of maximum scores, typically computed from the same ImpactsEnum

    • Method Detail

      • advance

        public int advance​(int target)
            throws IOException
        Description copied from class: DocIdSetIterator
        Advances to the first beyond the current whose document number is greater than or equal to target, and returns the document number itself. Exhausts the iterator and returns DocIdSetIterator.NO_MORE_DOCS if target is greater than the highest document number in the set.

        The behavior of this method is undefined when called with target ≤ current , or after the iterator has exhausted. Both cases may result in unpredicted behavior.

        When target > current it behaves as if written: 

         int advance(int target) {
   int doc;
   while ((doc = nextDoc()) < target) {
   }
   return doc;
 }
        Some implementations are considerably more efficient than that.

        NOTE: this method may be called with DocIdSetIterator.NO_MORE_DOCS for efficiency by some Scorers. If your implementation cannot efficiently determine that it should exhaust, it is recommended that you check for that value in each call to this method.

        Specified by:
        advance in class DocIdSetIterator
        Throws:
        IOException

      • cost

        public long cost()
        Description copied from class: DocIdSetIterator
        Returns the estimated cost of this DocIdSetIterator.

        This is generally an upper bound of the number of documents this iterator might match, but may be a rough heuristic, hardcoded value, or otherwise completely inaccurate.

        Specified by:
        cost in class DocIdSetIterator