Package org.apache.lucene.search

Class DisjunctionMaxQuery.DisjunctionMaxWeight

java.lang.Object

org.apache.lucene.search.Weight

org.apache.lucene.search.DisjunctionMaxQuery.DisjunctionMaxWeight

Enclosing class:

DisjunctionMaxQuery

protected class DisjunctionMaxQuery.DisjunctionMaxWeight
extends Weight

Expert: the Weight for DisjunctionMaxQuery, used to normalize, score and explain these queries.

NOTE: this API and implementation is subject to change suddenly in the next release.

Field Summary

Fields

Modifier and Type	Field	Description
protected ArrayList<Weight>	weights	The Weights for our subqueries, in 1-1 correspondence with disjuncts

Constructor Summary

Constructors

Constructor	Description
DisjunctionMaxWeight(IndexSearcher searcher)	Construct the Weight for this Query searched by searcher.

Method Summary

Modifier and Type	Method	Description
Explanation	explain(AtomicReaderContext context, int doc)	Explain the score we computed for doc
Query	getQuery()	Return our associated DisjunctionMaxQuery
float	getValueForNormalization()	Compute the sub of squared weights of us applied to our subqueries.
void	normalize(float norm, float topLevelBoost)	Apply the computed normalization factor to our subqueries
Scorer	scorer(AtomicReaderContext context, boolean scoreDocsInOrder, boolean topScorer, Bits acceptDocs)	Create the scorer used to score our associated DisjunctionMaxQuery

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

scoresDocsOutOfOrder

Methods inherited from class java.lang.Object

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

Field Detail

weights

protected ArrayList<Weight> weights

The Weights for our subqueries, in 1-1 correspondence with disjuncts

Constructor Detail

DisjunctionMaxWeight

public DisjunctionMaxWeight(IndexSearcher searcher)
                     throws IOException

Construct the Weight for this Query searched by searcher. Recursively construct subquery weights.

Throws:

IOException

Method Detail

getQuery

public Query getQuery()

Return our associated DisjunctionMaxQuery

Specified by:

getQuery in class Weight

getValueForNormalization

public float getValueForNormalization()
                               throws IOException

Compute the sub of squared weights of us applied to our subqueries. Used for normalization.

Specified by:

getValueForNormalization in class Weight

Throws:

IOException

normalize

public void normalize(float norm,
                      float topLevelBoost)

Apply the computed normalization factor to our subqueries

Specified by:

normalize in class Weight

scorer

public Scorer scorer(AtomicReaderContext context,
                     boolean scoreDocsInOrder,
                     boolean topScorer,
                     Bits acceptDocs)
              throws IOException

Create the scorer used to score our associated DisjunctionMaxQuery

Specified by:

scorer in class Weight

Parameters:

context - the AtomicReaderContext for which to return the Scorer.

scoreDocsInOrder - specifies whether in-order scoring of documents is required. Note that if set to false (i.e., out-of-order scoring is required), this method can return whatever scoring mode it supports, as every in-order scorer is also an out-of-order one. However, an out-of-order scorer may not support DocIdSetIterator.nextDoc() and/or DocIdSetIterator.advance(int), therefore it is recommended to request an in-order scorer if use of these methods is required.

topScorer - if true, Scorer.score(Collector) will be called; if false, DocIdSetIterator.nextDoc() and/or DocIdSetIterator.advance(int) will be called.

acceptDocs - Bits that represent the allowable docs to match (typically deleted docs but possibly filtering other documents)

Returns:

a Scorer which scores documents in/out-of order.

Throws:

IOException - if there is a low-level I/O error

explain

public Explanation explain(AtomicReaderContext context,
                           int doc)
                    throws IOException

Explain the score we computed for doc

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