Package org.apache.lucene.search

Class DisjunctionDISIApproximation

java.lang.Object
org.apache.lucene.search.DocIdSetIterator
org.apache.lucene.search.DisjunctionDISIApproximation
public final class DisjunctionDISIApproximation extends DocIdSetIterator
A DocIdSetIterator which is a disjunction of the approximations of the provided iterators.
NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

  • Constructor Details

    • DisjunctionDISIApproximation

      public DisjunctionDISIApproximation(Collection<? extends DisiWrapper> subIterators, long leadCost)

  • Method Details

    • of

      public static DisjunctionDISIApproximation of(Collection<? extends DisiWrapper> subIterators, long leadCost)

    • 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

    • docID

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

    • 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

    • 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

    • intoBitSet

      public void intoBitSet(int upTo, FixedBitSet bitSet, int offset) throws IOException
      Description copied from class: DocIdSetIterator
      Load doc IDs into a FixedBitSet. This should behave exactly as if implemented as below, which is the default implementation: 
       for (int doc = docID(); doc < upTo; doc = nextDoc()) {
   bitSet.set(doc - offset);
 }

      Note: offset must be less than or equal to the current doc ID. Behaviour is undefined if this iterator is unpositioned.

      Note: It is important not to clear bits from bitSet that may be already set.

      Note: offset may be negative.

      Overrides:
      intoBitSet in class DocIdSetIterator
      Throws:
      IOException

    • topList

      public DisiWrapper topList()
      Return the linked list of iterators positioned on the current doc.

    • docIDRunEnd

      public int docIDRunEnd() throws IOException
      Description copied from class: DocIdSetIterator
      Returns the end of the run of consecutive doc IDs that match this DocIdSetIterator and that contains the current DocIdSetIterator.docID(), that is: one plus the last doc ID of the run.
      1. The returned doc is greater than DocIdSetIterator.docID().
      2. All docs in range [docID(), docIDRunEnd()) match this iterator.
      3. The current position of this iterator is not affected by calling DocIdSetIterator.docIDRunEnd().

      Note: It is illegal to call this method when the iterator is exhausted or not positioned.

      The default implementation assumes runs of a single doc ID and returns DocIdSetIterator.docID()) + 1.

      Overrides:
      docIDRunEnd in class DocIdSetIterator
      Throws:
      IOException