Module org.apache.lucene.core

Package org.apache.lucene.search

Class MultiTermQueryConstantScoreBlendedWrapper<Q extends MultiTermQuery>

java.lang.Object

org.apache.lucene.search.Query

org.apache.lucene.search.AbstractMultiTermQueryConstantScoreWrapper<Q>

org.apache.lucene.search.MultiTermQueryConstantScoreBlendedWrapper<Q>

All Implemented Interfaces:

Accountable

final class MultiTermQueryConstantScoreBlendedWrapper<Q extends MultiTermQuery>
extends AbstractMultiTermQueryConstantScoreWrapper<Q>

This class provides the functionality behind MultiTermQuery.CONSTANT_SCORE_BLENDED_REWRITE. It maintains a boolean query-like approach over a limited number of the most costly terms while rewriting the remaining terms into a filter bitset.

Nested Class Summary

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

AbstractMultiTermQueryConstantScoreWrapper.RewritingWeight, AbstractMultiTermQueryConstantScoreWrapper.TermAndState, AbstractMultiTermQueryConstantScoreWrapper.WeightOrDocIdSetIterator

Field Summary

Fields

Modifier and Type	Field	Description
private static final int	POSTINGS_PRE_PROCESS_THRESHOLD

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

BOOLEAN_REWRITE_TERM_COUNT_THRESHOLD, query

Fields inherited from interface org.apache.lucene.util.Accountable

NULL_ACCOUNTABLE

Constructor Summary

Constructors

Constructor	Description
MultiTermQueryConstantScoreBlendedWrapper(Q query)

Method Summary

Modifier and Type	Method	Description
Weight	createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost)	Expert: Constructs an appropriate Weight implementation for this query.
private static Scorer	wrapWithDummyScorer(Weight weight, DocIdSetIterator disi)	Wraps a DISI with a "dummy" scorer so we can easily use DisiWrapper and DisjunctionDISIApproximation as-is.

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

equals, getField, getQuery, hashCode, ramBytesUsed, toString, visit

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

classHash, rewrite, rewrite, sameClassAs, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.lucene.util.Accountable

getChildResources

Field Details

POSTINGS_PRE_PROCESS_THRESHOLD

private static final int POSTINGS_PRE_PROCESS_THRESHOLD

See Also:

• Constant Field Values

Constructor Details

MultiTermQueryConstantScoreBlendedWrapper

MultiTermQueryConstantScoreBlendedWrapper(Q query)

Method Details

createWeight

public Weight createWeight(IndexSearcher searcher,
 ScoreMode scoreMode,
 float boost)
                    throws IOException

Description copied from class: Query

Expert: Constructs an appropriate Weight implementation for this query.

Only implemented by primitive queries, which re-write to themselves.

Overrides:

createWeight in class Query

Parameters:

scoreMode - How the produced scorers will be consumed.

boost - The boost that is propagated by the parent queries.

Throws:

IOException

wrapWithDummyScorer

private static Scorer wrapWithDummyScorer(Weight weight,
 DocIdSetIterator disi)

Wraps a DISI with a "dummy" scorer so we can easily use DisiWrapper and DisjunctionDISIApproximation as-is. This is really just a convenient vehicle to get the DISI into the priority queue used by DisjunctionDISIApproximation. The Scorer ultimately provided by the weight provides a constant boost and reflects the actual score mode.