org.apache.lucene.search
public abstract class Scorer extends Object
Scorer
either iterates over documents matching a query,
or provides an explanation of the score for a query for a given document.
Similarity
implementation.
Constructor Summary | |
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protected | Scorer(Similarity similarity) Constructs a Scorer. |
Method Summary | |
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abstract int | doc() Returns the current document number matching the query.
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abstract Explanation | explain(int doc) Returns an explanation of the score for a document.
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Similarity | getSimilarity() Returns the Similarity implementation used by this scorer. |
abstract boolean | next() Advances to the next document matching the query. |
void | score(HitCollector hc) Scores and collects all matching documents. |
protected boolean | score(HitCollector hc, int max) Expert: Collects matching documents in a range. |
abstract float | score() Returns the score of the current document matching the query.
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abstract boolean | skipTo(int target) Skips to the first match beyond the current whose document number is
greater than or equal to a given target.
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Parameters: similarity The Similarity
implementation used by this scorer.
Parameters: doc The document number for the explanation.
Returns: true iff there is another document matching the query.
When this method is used the Scorer method should not be used.
Parameters: hc The collector to which all matching documents are passed through
HitCollector.
When this method is used the Scorer method should not be used.
Parameters: hc The collector to which all matching documents are passed through HitCollector. max Do not score documents past this.
Returns: true if more matching documents may remain.
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.