Module org.apache.lucene.queries

Package org.apache.lucene.queries.function

Class FunctionScoreQuery.FunctionScoreWeight

java.lang.Object

org.apache.lucene.search.Weight

org.apache.lucene.queries.function.FunctionScoreQuery.FunctionScoreWeight

All Implemented Interfaces:

SegmentCacheable

Enclosing class:

FunctionScoreQuery

private static class FunctionScoreQuery.FunctionScoreWeight
extends Weight

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.search.Weight

Weight.DefaultBulkScorer

Field Summary

Fields

Modifier and Type	Field	Description
(package private) final float	boost
(package private) final Weight	inner
(package private) final DoubleValuesSource	valueSource

Fields inherited from class org.apache.lucene.search.Weight

parentQuery

Constructor Summary

Constructors

Constructor	Description
FunctionScoreWeight(Query query, Weight inner, DoubleValuesSource valueSource, float boost)

Method Summary

Modifier and Type	Method	Description
int	count(LeafReaderContext context)	Counts the number of live documents that match a given Weight.parentQuery in a leaf.
Explanation	explain(LeafReaderContext context, int doc)	An explanation of the score computation for the named document.
boolean	isCacheable(LeafReaderContext ctx)
Matches	matches(LeafReaderContext context, int doc)	Returns Matches for a specific document, or null if the document does not match the parent query
Scorer	scorer(LeafReaderContext context)	Returns a Scorer which can iterate in order over all matching documents and assign them a score.

Methods inherited from class org.apache.lucene.search.Weight

bulkScorer, getQuery, scorerSupplier

Methods inherited from class java.lang.Object

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

Field Details

inner

final Weight inner

valueSource

final DoubleValuesSource valueSource

boost

final float boost

Constructor Details

FunctionScoreWeight

FunctionScoreWeight(Query query,
 Weight inner,
 DoubleValuesSource valueSource,
 float boost)

Method Details

matches

public Matches matches(LeafReaderContext context,
 int doc)
                throws IOException

Description copied from class: Weight

Returns Matches for a specific document, or null if the document does not match the parent query

A query match that contains no position information (for example, a Point or DocValues query) will return MatchesUtils.MATCH_WITH_NO_TERMS

Overrides:

matches in class Weight

Parameters:

context - the reader's context to create the Matches for

doc - the document's id relative to the given context's reader

Throws:

IOException

explain

public Explanation explain(LeafReaderContext context,
 int doc)
                    throws IOException

Description copied from class: Weight

An explanation of the score computation for the named document.

Specified by:

explain in class Weight

Parameters:

context - the readers context to create the Explanation for.

doc - the document's id relative to the given context's reader

Returns:

an Explanation for the score

Throws:

IOException - if an IOException occurs

scorer

public Scorer scorer(LeafReaderContext context)
              throws IOException

Description copied from class: Weight

Returns a Scorer which can iterate in order over all matching documents and assign them a score.

NOTE: null can be returned if no documents will be scored by this query.

NOTE: The returned Scorer does not have LeafReader.getLiveDocs() applied, they need to be checked on top.

Specified by:

scorer in class Weight

Parameters:

context - the LeafReaderContext for which to return the Scorer.

Returns:

a Scorer which scores documents in/out-of order.

Throws:

IOException - if there is a low-level I/O error

count

public int count(LeafReaderContext context)
          throws IOException

Description copied from class: Weight

Counts the number of live documents that match a given Weight.parentQuery in a leaf.

The default implementation returns -1 for every query. This indicates that the count could not be computed in sub-linear time.

Specific query classes should override it to provide other accurate sub-linear implementations (that actually return the count). Look at MatchAllDocsQuery.createWeight(IndexSearcher, ScoreMode, float) for an example

We use this property of the function to count hits in IndexSearcher.count(Query).

Overrides:

count in class Weight

Parameters:

context - the LeafReaderContext for which to return the count.

Returns:

integer count of the number of matches

Throws:

IOException - if there is a low-level I/O error

isCacheable

public boolean isCacheable(LeafReaderContext ctx)

Returns:

true if the object can be cached against a given leaf