Package org.apache.lucene.search

# Class MultiTermQuery.TopTermsBlendedFreqScoringRewrite

java.lang.Object
org.apache.lucene.search.MultiTermQuery.RewriteMethod
org.apache.lucene.search.TopTermsRewrite<BlendedTermQuery.Builder>
org.apache.lucene.search.MultiTermQuery.TopTermsBlendedFreqScoringRewrite

Enclosing class:
  `MultiTermQuery`

public static final class MultiTermQuery.TopTermsBlendedFreqScoringRewrite extends TopTermsRewrite<BlendedTermQuery.Builder>
A rewrite method that first translates each term into `BooleanClause.Occur.SHOULD` clause in a BooleanQuery, but adjusts the frequencies used for scoring to be blended across the terms, otherwise the rarest term typically ranks highest (often not useful eg in the set of expanded terms in a FuzzyQuery).

This rewrite method only uses the top scoring terms so it will not overflow the boolean max clause count.

## Constructor Summary

Constructors
Constructor
Description
`TopTermsBlendedFreqScoringRewrite(int size)`
Create a TopTermsBlendedScoringBooleanQueryRewrite for at most `size` terms.

## Method Summary

Modifier and Type
Method
Description
`protected final void`
`addClause(BlendedTermQuery.Builder topLevel, Term term, int docCount, float boost)`
Add a MultiTermQuery term to the top-level query builder.
`protected void`
`addClause(BlendedTermQuery.Builder topLevel, Term term, int docCount, float boost, TermStates states)`
`protected Query`
`build(BlendedTermQuery.Builder builder)`
Finalize the creation of the query from the builder.
`protected int`
`getMaxSize()`
return the maximum size of the priority queue (for boolean rewrites this is BooleanQuery#getMaxClauseCount).
`protected BlendedTermQuery.Builder`
`getTopLevelBuilder()`
Return a suitable builder for the 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 Details

### TopTermsBlendedFreqScoringRewrite

public TopTermsBlendedFreqScoringRewrite(int size)
Create a TopTermsBlendedScoringBooleanQueryRewrite for at most `size` terms.

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

## Method Details

### 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<BlendedTermQuery.Builder>`

### getTopLevelBuilder

protected BlendedTermQuery.Builder getTopLevelBuilder()
Return a suitable builder for the top-level Query for holding all expanded terms.

### build

protected Query build(BlendedTermQuery.Builder builder)
Finalize the creation of the query from the builder.

### addClause

protected void addClause(BlendedTermQuery.Builder topLevel, Term term, int docCount, float boost, TermStates states)

### addClause

protected final void addClause(BlendedTermQuery.Builder topLevel, Term term, int docCount, float boost) throws IOException
Add a MultiTermQuery term to the top-level query builder.

Throws:
  `IOException`