org.apache.lucene.facet.search

Class FacetsCollector

java.lang.Object

org.apache.lucene.search.Collector

org.apache.lucene.facet.search.FacetsCollector

public abstract class FacetsCollector
extends Collector

A Collector which executes faceted search and computes the weight of requested facets. To get the facet results you should call getFacetResults(). create(FacetSearchParams, IndexReader, TaxonomyReader) returns the most optimized FacetsCollector for the given parameters.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FacetsCollector.MatchingDocs Holds the documents that were matched in the AtomicReaderContext.

Field Summary

Fields

Modifier and Type	Field and Description
protected List<FacetsCollector.MatchingDocs>	matchingDocs

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FacetsCollector(FacetsAccumulator accumulator)

Method Summary

Methods

Modifier and Type	Method and Description
static FacetsCollector	create(FacetsAccumulator accumulator) Creates a FacetsCollector that satisfies the requirements of the given FacetsAccumulator.
static FacetsCollector	create(FacetSearchParams fsp, IndexReader indexReader, TaxonomyReader taxoReader) Creates a FacetsCollector using the FacetsAccumulator from FacetsAccumulator.create(org.apache.lucene.facet.params.FacetSearchParams, org.apache.lucene.index.IndexReader, org.apache.lucene.facet.taxonomy.TaxonomyReader).
protected abstract void	doSetNextReader(AtomicReaderContext context) Performs the actual work of setNextReader(AtomicReaderContext).
protected abstract void	finish() Called when the Collector has finished, so that the last FacetsCollector.MatchingDocs can be added.
List<FacetResult>	getFacetResults() Returns a FacetResult per FacetRequest set in FacetSearchParams.
List<FacetsCollector.MatchingDocs>	getMatchingDocs() Returns the documents matched by the query, one FacetsCollector.MatchingDocs per visited segment.
void	reset() Allows to reuse the collector between search requests.
void	setNextReader(AtomicReaderContext context)

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

acceptsDocsOutOfOrder, collect, setScorer

Methods inherited from class java.lang.Object

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

Field Detail

matchingDocs

protected final List<FacetsCollector.MatchingDocs> matchingDocs

Constructor Detail

FacetsCollector

protected FacetsCollector(FacetsAccumulator accumulator)

Method Detail

create

public static FacetsCollector create(FacetSearchParams fsp,
                     IndexReader indexReader,
                     TaxonomyReader taxoReader)

Creates a FacetsCollector using the FacetsAccumulator from FacetsAccumulator.create(org.apache.lucene.facet.params.FacetSearchParams, org.apache.lucene.index.IndexReader, org.apache.lucene.facet.taxonomy.TaxonomyReader).

create

public static FacetsCollector create(FacetsAccumulator accumulator)

Creates a FacetsCollector that satisfies the requirements of the given FacetsAccumulator.

finish

protected abstract void finish()

Called when the Collector has finished, so that the last FacetsCollector.MatchingDocs can be added.

doSetNextReader

protected abstract void doSetNextReader(AtomicReaderContext context)
                                 throws IOException

Performs the actual work of setNextReader(AtomicReaderContext).

Throws:

IOException

getFacetResults

public final List<FacetResult> getFacetResults()
                                        throws IOException

Returns a FacetResult per FacetRequest set in FacetSearchParams. Note that if a FacetRequest defines a CategoryPath which does not exist in the taxonomy, an empty FacetResult will be returned for it.

Throws:

IOException

getMatchingDocs

public final List<FacetsCollector.MatchingDocs> getMatchingDocs()

Returns the documents matched by the query, one FacetsCollector.MatchingDocs per visited segment.

reset

public final void reset()

Allows to reuse the collector between search requests. This method simply clears all collected documents (and scores) information (as well as cached results), and does not attempt to reuse allocated memory spaces.

setNextReader

public final void setNextReader(AtomicReaderContext context)
                         throws IOException

Specified by:

setNextReader in class Collector

Throws:

IOException