org.apache.lucene.search.similarities

Class Similarity.SimScorer

java.lang.Object

org.apache.lucene.search.similarities.Similarity.SimScorer

Enclosing class:

Similarity

public abstract static class Similarity.SimScorer
extends Object

API for scoring "sloppy" queries such as TermQuery, SpanQuery, and PhraseQuery.

Frequencies are floating-point values: an approximate within-document frequency adjusted for "sloppiness" by computeSlopFactor(int).

Constructor Summary

Constructors

Constructor and Description
Similarity.SimScorer() Sole constructor.

Method Summary

Methods

Modifier and Type	Method and Description
abstract float	computePayloadFactor(int doc, int start, int end, BytesRef payload) Calculate a scoring factor based on the data in the payload.
abstract float	computeSlopFactor(int distance) Computes the amount of a sloppy phrase match, based on an edit distance.
Explanation	explain(int doc, Explanation freq) Explain the score for a single document
abstract float	score(int doc, float freq) Score a single document

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Similarity.SimScorer

public Similarity.SimScorer()

Sole constructor. (For invocation by subclass constructors, typically implicit.)

Method Detail

score

public abstract float score(int doc,
          float freq)

Score a single document

Parameters:

doc - document id within the inverted index segment

freq - sloppy term frequency

Returns:

document's score

computeSlopFactor

public abstract float computeSlopFactor(int distance)

Computes the amount of a sloppy phrase match, based on an edit distance.

computePayloadFactor

public abstract float computePayloadFactor(int doc,
                         int start,
                         int end,
                         BytesRef payload)

Calculate a scoring factor based on the data in the payload.

explain

public Explanation explain(int doc,
                  Explanation freq)

Explain the score for a single document

Parameters:

doc - document id within the inverted index segment

freq - Explanation of how the sloppy term frequency was computed

Returns:

document's score