org.apache.lucene.search
Class ConstantScoreQuery.ConstantScorer

java.lang.Object
  extended byorg.apache.lucene.search.Scorer
      extended byorg.apache.lucene.search.ConstantScoreQuery.ConstantScorer
Enclosing class:
ConstantScoreQuery

protected class ConstantScoreQuery.ConstantScorer
extends Scorer


Constructor Summary
ConstantScoreQuery.ConstantScorer(Similarity similarity, IndexReader reader, Weight w)
           
 
Method Summary
 int doc()
          Returns the current document number matching the query.
 Explanation explain(int doc)
          Returns an explanation of the score for a document.
 boolean next()
          Advances to the next document matching the query.
 float score()
          Returns the score of the current document matching the query.
 boolean skipTo(int target)
          Skips to the first match beyond the current whose document number is greater than or equal to a given target.
 
Methods inherited from class org.apache.lucene.search.Scorer
getSimilarity, score, score
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ConstantScoreQuery.ConstantScorer

public ConstantScoreQuery.ConstantScorer(Similarity similarity,
                                         IndexReader reader,
                                         Weight w)
                                  throws IOException
Method Detail

next

public boolean next()
             throws IOException
Description copied from class: Scorer
Advances to the next document matching the query.

Specified by:
next in class Scorer
Returns:
true iff there is another document matching the query.
When this method is used the Scorer.explain(int) method should not be used.
Throws:
IOException

doc

public int doc()
Description copied from class: Scorer
Returns the current document number matching the query. Initially invalid, until Scorer.next() is called the first time.

Specified by:
doc in class Scorer

score

public float score()
            throws IOException
Description copied from class: Scorer
Returns the score of the current document matching the query. Initially invalid, until Scorer.next() or Scorer.skipTo(int) is called the first time.

Specified by:
score in class Scorer
Throws:
IOException

skipTo

public boolean skipTo(int target)
               throws IOException
Description copied from class: Scorer
Skips to the first match beyond the current whose document number is greater than or equal to a given target.
When this method is used the Scorer.explain(int) method should not be used.

Specified by:
skipTo in class Scorer
Parameters:
target - The target document number.
Returns:
true iff there is such a match.

Behaves as if written:

   boolean skipTo(int target) {
     do {
       if (!next())
 	     return false;
     } while (target > doc());
     return true;
   }
 
Most implementations are considerably more efficient than that.
Throws:
IOException

explain

public Explanation explain(int doc)
                    throws IOException
Description copied from class: Scorer
Returns an explanation of the score for a document.
When this method is used, the Scorer.next(), Scorer.skipTo(int) and Scorer.score(HitCollector) methods should not be used.

Specified by:
explain in class Scorer
Parameters:
doc - The document number for the explanation.
Throws:
IOException


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