org.apache.lucene.search
Class MultiTermQuery.TopTermsScoringBooleanQueryRewrite

java.lang.Object
  org.apache.lucene.search.MultiTermQuery.RewriteMethod
      org.apache.lucene.search.TopTermsRewrite<BooleanQuery>
          org.apache.lucene.search.MultiTermQuery.TopTermsScoringBooleanQueryRewrite

All Implemented Interfaces:

Serializable

Enclosing class:

MultiTermQuery

public static final class MultiTermQuery.TopTermsScoringBooleanQueryRewrite
extends TopTermsRewrite<BooleanQuery>

A rewrite method that first translates each term into BooleanClause.Occur.SHOULD clause in a BooleanQuery, and keeps the scores as computed by the query.

This rewrite method only uses the top scoring terms so it will not overflow the boolean max clause count. It is the default rewrite method for FuzzyQuery.

See Also:

MultiTermQuery.setRewriteMethod(org.apache.lucene.search.MultiTermQuery.RewriteMethod), Serialized Form

Nested Class Summary

protected static interface

TermCollectingRewrite.TermCollector

Constructor Summary

MultiTermQuery.TopTermsScoringBooleanQueryRewrite(int size)
Create a TopTermsScoringBooleanQueryRewrite for at most size terms.

Method Summary

protected void	addClause(BooleanQuery topLevel, Term term, float boost) Add a MultiTermQuery term to the top-level query
protected void	collectTerms(IndexReader reader, MultiTermQuery query, TermCollectingRewrite.TermCollector collector)
protected int	getMaxSize() return the maximum size of the priority queue (for boolean rewrites this is BooleanQuery#getMaxClauseCount).
protected BooleanQuery	getTopLevelQuery() Return a suitable top-level Query for holding all expanded terms.

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

equals, getSize, hashCode, rewrite

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

Constructor Detail

MultiTermQuery.TopTermsScoringBooleanQueryRewrite

public MultiTermQuery.TopTermsScoringBooleanQueryRewrite(int size)

Create a TopTermsScoringBooleanQueryRewrite for at most size terms.

NOTE: if BooleanQuery.getMaxClauseCount() is smaller than size, then it will be used instead.

Method Detail

getMaxSize

protected int getMaxSize()

Description copied from class: TopTermsRewrite

return the maximum size of the priority queue (for boolean rewrites this is BooleanQuery#getMaxClauseCount).

Specified by:

getMaxSize in class TopTermsRewrite<BooleanQuery>

getTopLevelQuery

protected BooleanQuery getTopLevelQuery()

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

addClause

protected void addClause(BooleanQuery topLevel,
                         Term term,
                         float boost)

Add a MultiTermQuery term to the top-level query

collectTerms

protected final void collectTerms(IndexReader reader,
                                  MultiTermQuery query,
                                  TermCollectingRewrite.TermCollector collector)
                           throws IOException

Throws:

IOException