Module org.apache.lucene.core

Package org.apache.lucene.search

Class TermQuery.TermWeight

java.lang.Object

org.apache.lucene.search.Weight

org.apache.lucene.search.TermQuery.TermWeight

All Implemented Interfaces:

SegmentCacheable

Enclosing class:

TermQuery

final class TermQuery.TermWeight
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
private final ScoreMode	scoreMode
private final Similarity	similarity
private final Similarity.SimScorer	simScorer
private final TermStates	termStates

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

parentQuery

Constructor Summary

Constructors

Constructor	Description
TermWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost, TermStates termStates)

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.
private TermsEnum	getTermsEnum(LeafReaderContext context)	Returns a TermsEnum positioned at this weights Term or null if the term does not exist in the given context
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.
ScorerSupplier	scorerSupplier(LeafReaderContext context)	Optional method.
private boolean	termNotInReader(LeafReader reader, Term term)
String	toString()

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

bulkScorer, getQuery

Methods inherited from class java.lang.Object

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

Field Details

similarity

private final Similarity similarity

simScorer

private final Similarity.SimScorer simScorer

termStates

private final TermStates termStates

scoreMode

private final ScoreMode scoreMode

Constructor Details

TermWeight

public TermWeight(IndexSearcher searcher,
 ScoreMode scoreMode,
 float boost,
 TermStates termStates)
           throws IOException

Throws:

IOException

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

toString

public String toString()

Overrides:

toString in class Object

scorerSupplier

public ScorerSupplier scorerSupplier(LeafReaderContext context)
                              throws IOException

Description copied from class: Weight

Optional method. Get a ScorerSupplier, which allows to know the cost of the Scorer before building it. The default implementation calls Weight.scorer(org.apache.lucene.index.LeafReaderContext) and builds a ScorerSupplier wrapper around it.

Overrides:

scorerSupplier in class Weight

Throws:

IOException

See Also:

• Weight.scorer(org.apache.lucene.index.LeafReaderContext)

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

isCacheable

public boolean isCacheable(LeafReaderContext ctx)

Returns:

true if the object can be cached against a given leaf

getTermsEnum

private TermsEnum getTermsEnum(LeafReaderContext context)
                        throws IOException

Returns a TermsEnum positioned at this weights Term or null if the term does not exist in the given context

Throws:

IOException

termNotInReader

private boolean termNotInReader(LeafReader reader,
 Term term)
                         throws IOException

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

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