Class ImpactsDISI

java.lang.Object
org.apache.lucene.search.DocIdSetIterator
org.apache.lucene.search.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 Details

    • 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 Details

    • getMaxScoreCache

      public MaxScoreCache getMaxScoreCache()
      Get the MaxScoreCache.
    • setMinCompetitiveScore

      public void setMinCompetitiveScore(float minCompetitiveScore)
      Set the minimum competitive score.
      See Also:
    • 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
    • nextDoc

      public int nextDoc() throws IOException
      Description copied from class: DocIdSetIterator
      Advances to the next document in the set and returns the doc it is currently on, or DocIdSetIterator.NO_MORE_DOCS if there are no more docs in the set.
      NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.
      Specified by:
      nextDoc in class DocIdSetIterator
      Throws:
      IOException
    • docID

      public int docID()
      Description copied from class: DocIdSetIterator
      Returns the following:
      Specified by:
      docID in class DocIdSetIterator
    • 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