Package org.apache.lucene.search

Class LargeNumHitsTopDocsCollector

java.lang.Object

org.apache.lucene.search.LargeNumHitsTopDocsCollector

All Implemented Interfaces:

Collector

public final class LargeNumHitsTopDocsCollector
extends java.lang.Object
implements Collector

Optimized collector for large number of hits. The collector maintains an ArrayList of hits until it accumulates the requested number of hits. Post that, it builds a Priority Queue and starts filtering further hits based on the minimum competitive score.

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.List<ScoreDoc>	hits
(package private) HitQueue	pq
(package private) ScoreDoc	pqTop
private int	requestedHitCount
(package private) int	totalHits

Constructor Summary

Constructors

Constructor	Description
LargeNumHitsTopDocsCollector(int requestedHitCount)

Method Summary

Modifier and Type	Method	Description
LeafCollector	getLeafCollector(LeafReaderContext context)	Create a new collector to collect the given context.
protected TopDocs	newTopDocs(ScoreDoc[] results)	Returns a TopDocs instance containing the given results.
protected void	populateResults(ScoreDoc[] results, int howMany)	Populates the results array with the ScoreDoc instances.
ScoreMode	scoreMode()	Indicates what features are required from the scorer.
TopDocs	topDocs()	Returns the top docs that were collected by this collector.
TopDocs	topDocs(int howMany)	Returns the top docs that were collected by this collector.

Methods inherited from class java.lang.Object

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

Field Detail

requestedHitCount

private final int requestedHitCount

hits

private java.util.List<ScoreDoc> hits

pq

HitQueue pq

pqTop

ScoreDoc pqTop

totalHits

int totalHits

Constructor Detail

LargeNumHitsTopDocsCollector

public LargeNumHitsTopDocsCollector(int requestedHitCount)

Method Detail

scoreMode

public ScoreMode scoreMode()

Description copied from interface: Collector

Indicates what features are required from the scorer.

Specified by:

scoreMode in interface Collector

getLeafCollector

public LeafCollector getLeafCollector(LeafReaderContext context)

Description copied from interface: Collector

Create a new collector to collect the given context.

Specified by:

getLeafCollector in interface Collector

Parameters:

context - next atomic reader context

topDocs

public TopDocs topDocs(int howMany)

Returns the top docs that were collected by this collector.

populateResults

protected void populateResults(ScoreDoc[] results,
                               int howMany)

Populates the results array with the ScoreDoc instances. This can be overridden in case a different ScoreDoc type should be returned.

newTopDocs

protected TopDocs newTopDocs(ScoreDoc[] results)

Returns a TopDocs instance containing the given results. If results is null it means there are no results to return, either because there were 0 calls to collect() or because the arguments to topDocs were invalid.

topDocs

public TopDocs topDocs()

Returns the top docs that were collected by this collector.