Package org.apache.lucene.search

Class MultiTermQuery.ConstantScoreAutoRewrite

java.lang.Object

org.apache.lucene.search.MultiTermQuery.RewriteMethod

org.apache.lucene.search.MultiTermQuery.ConstantScoreAutoRewrite

Enclosing class:

MultiTermQuery

public static class MultiTermQuery.ConstantScoreAutoRewrite
extends MultiTermQuery.RewriteMethod

A rewrite method that tries to pick the best constant-score rewrite method based on term and document counts from the query. If both the number of terms and documents is small enough, then MultiTermQuery.CONSTANT_SCORE_BOOLEAN_QUERY_REWRITE is used. Otherwise, MultiTermQuery.CONSTANT_SCORE_FILTER_REWRITE is used.

Field Summary

Fields

Modifier and Type	Field	Description
static double	DEFAULT_DOC_COUNT_PERCENT
static int	DEFAULT_TERM_COUNT_CUTOFF

Constructor Summary

Constructors

Constructor	Description
ConstantScoreAutoRewrite()

Method Summary

Modifier and Type	Method	Description
protected void	addClause(BooleanQuery topLevel, Term term, int docFreq, float boost, TermContext states)
protected void	addClause(Q topLevel, Term term, int docCount, float boost)	Add a MultiTermQuery term to the top-level query
boolean	equals(Object obj)
double	getDocCountPercent()
int	getTermCountCutoff()
protected BooleanQuery	getTopLevelQuery()	Return a suitable top-level Query for holding all expanded terms.
int	hashCode()
Query	rewrite(IndexReader reader, MultiTermQuery query)
void	setDocCountPercent(double percent)	If the number of documents to be visited in the postings exceeds this specified percentage of the maxDoc() for the index, then MultiTermQuery.CONSTANT_SCORE_FILTER_REWRITE is used.
void	setTermCountCutoff(int count)	If the number of terms in this query is equal to or larger than this setting then MultiTermQuery.CONSTANT_SCORE_FILTER_REWRITE is used.

Methods inherited from class org.apache.lucene.search.MultiTermQuery.RewriteMethod

getTermsEnum

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_TERM_COUNT_CUTOFF

public static int DEFAULT_TERM_COUNT_CUTOFF

DEFAULT_DOC_COUNT_PERCENT

public static double DEFAULT_DOC_COUNT_PERCENT

Constructor Detail

ConstantScoreAutoRewrite

public ConstantScoreAutoRewrite()

Method Detail

setTermCountCutoff

public void setTermCountCutoff(int count)

If the number of terms in this query is equal to or larger than this setting then MultiTermQuery.CONSTANT_SCORE_FILTER_REWRITE is used.

getTermCountCutoff

public int getTermCountCutoff()

See Also:

setTermCountCutoff(int)

setDocCountPercent

public void setDocCountPercent(double percent)

If the number of documents to be visited in the postings exceeds this specified percentage of the maxDoc() for the index, then MultiTermQuery.CONSTANT_SCORE_FILTER_REWRITE is used.

Parameters:

percent - 0.0 to 100.0

getDocCountPercent

public double getDocCountPercent()

See Also:

setDocCountPercent(double)

getTopLevelQuery

protected BooleanQuery getTopLevelQuery()

Return a suitable top-level Query for holding all expanded terms.

addClause

protected void addClause(BooleanQuery topLevel,
                         Term term,
                         int docFreq,
                         float boost,
                         TermContext states)

rewrite

public Query rewrite(IndexReader reader,
                     MultiTermQuery query)
              throws IOException

Specified by:

rewrite in class MultiTermQuery.RewriteMethod

Throws:

IOException

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

addClause

protected final void addClause(Q topLevel,
                               Term term,
                               int docCount,
                               float boost)
                        throws IOException

Add a MultiTermQuery term to the top-level query

Throws:

IOException