Module org.apache.lucene.queries

Package org.apache.lucene.queries.spans

Class SpanWeight

java.lang.Object

org.apache.lucene.search.Weight

org.apache.lucene.queries.spans.SpanWeight

All Implemented Interfaces:

SegmentCacheable

Direct Known Subclasses:

PayloadScoreQuery.PayloadSpanWeight, SpanContainQuery.SpanContainWeight, SpanNearQuery.SpanGapQuery.SpanGapWeight, SpanNearQuery.SpanNearWeight, SpanNotQuery.SpanNotWeight, SpanOrQuery.SpanOrWeight, SpanPayloadCheckQuery.SpanPayloadCheckWeight, SpanPositionCheckQuery.SpanPositionCheckWeight, SpanTermQuery.SpanTermWeight

public abstract class SpanWeight
extends Weight

Expert-only. Public for use by other weight implementations

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	SpanWeight.Postings	Enumeration defining what postings information should be retrieved from the index for a given Spans
private static class	SpanWeight.TermMatch

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

Weight.DefaultBulkScorer, Weight.DefaultScorerSupplier

Field Summary

Fields

Modifier and Type	Field	Description
protected final String	field
protected final Similarity	similarity
protected final Similarity.SimScorer	simScorer

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

parentQuery

Constructor Summary

Constructors

Constructor	Description
SpanWeight(SpanQuery query, IndexSearcher searcher, Map<Term,TermStates> termStates, float boost)	Create a new SpanWeight

Method Summary

Modifier and Type	Method	Description
private Similarity.SimScorer	buildSimWeight(SpanQuery query, IndexSearcher searcher, Map<Term,TermStates> termStates, float boost)
Explanation	explain(LeafReaderContext context, int doc)	An explanation of the score computation for the named document.
abstract void	extractTermStates(Map<Term,TermStates> contexts)	Collect all TermStates used by this Weight
Similarity.SimScorer	getSimScorer()	Return the SimScorer
abstract Spans	getSpans(LeafReaderContext ctx, SpanWeight.Postings requiredPostings)	Expert: Return a Spans object iterating over matches from this Weight
Matches	matches(LeafReaderContext context, int doc)	Returns Matches for a specific document, or null if the document does not match the parent query
ScorerSupplier	scorerSupplier(LeafReaderContext context)	Get a ScorerSupplier, which allows knowing the cost of the Scorer before building it.

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

bulkScorer, count, getQuery, scorer

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.lucene.search.SegmentCacheable

isCacheable

Field Details

similarity

protected final Similarity similarity

simScorer

protected final Similarity.SimScorer simScorer

field

protected final String field

Constructor Details

SpanWeight

public SpanWeight(SpanQuery query,
 IndexSearcher searcher,
 Map<Term,TermStates> termStates,
 float boost)
           throws IOException

Create a new SpanWeight

Parameters:

query - the parent query

searcher - the IndexSearcher to query against

termStates - a map of terms to TermStates for use in building the similarity. May be null if scores are not required

Throws:

IOException - on error

Method Details

buildSimWeight

private Similarity.SimScorer buildSimWeight(SpanQuery query,
 IndexSearcher searcher,
 Map<Term,TermStates> termStates,
 float boost)
                                     throws IOException

Throws:

IOException

extractTermStates

public abstract void extractTermStates(Map<Term,TermStates> contexts)

Collect all TermStates used by this Weight

Parameters:

contexts - a map to add the TermStates to

getSpans

public abstract Spans getSpans(LeafReaderContext ctx,
 SpanWeight.Postings requiredPostings)
                        throws IOException

Expert: Return a Spans object iterating over matches from this Weight

Parameters:

ctx - a LeafReaderContext for this Spans

Returns:

a Spans

Throws:

IOException - on error

scorerSupplier

public ScorerSupplier scorerSupplier(LeafReaderContext context)
                              throws IOException

Description copied from class: Weight

Get a ScorerSupplier, which allows knowing the cost of the Scorer before building it. A scorer supplier for the same LeafReaderContext instance may be requested multiple times as part of a single search call.

Note: It must return null if the scorer is null.

Specified by:

scorerSupplier in class Weight

Parameters:

context - the leaf reader context

Returns:

a ScorerSupplier providing the scorer, or null if scorer is null

Throws:

IOException - if an IOException occurs

See Also:

• Scorer
• Weight.DefaultScorerSupplier

getSimScorer

public Similarity.SimScorer getSimScorer()

Return the SimScorer

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

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