org.apache.lucene.facet.search

Class FacetsAccumulator

java.lang.Object

org.apache.lucene.facet.search.FacetsAccumulator

Direct Known Subclasses:

SortedSetDocValuesAccumulator, StandardFacetsAccumulator

public class FacetsAccumulator
extends Object

Driver for Accumulating facets of faceted search requests over given documents.

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

Field Summary

Fields

Modifier and Type	Field and Description
FacetArrays	facetArrays
IndexReader	indexReader
FacetSearchParams	searchParams
TaxonomyReader	taxonomyReader

Constructor Summary

Constructors

Constructor and Description
FacetsAccumulator(FacetSearchParams searchParams, IndexReader indexReader, TaxonomyReader taxonomyReader) Initializes the accumulator with the given search params, index reader and taxonomy reader.
FacetsAccumulator(FacetSearchParams searchParams, IndexReader indexReader, TaxonomyReader taxonomyReader, FacetArrays facetArrays) Initializes the accumulator with the given parameters as well as FacetArrays.

Method Summary

Methods

Modifier and Type	Method and Description
List<FacetResult>	accumulate(List<FacetsCollector.MatchingDocs> matchingDocs) Used by FacetsCollector to build the list of facet results that match the facet requests that were given in the constructor.
static FacetsAccumulator	create(FacetSearchParams fsp, IndexReader indexReader, TaxonomyReader taxoReader) Creates an appropriate FacetsAccumulator, returning FacetsAccumulator when all requests are CountFacetRequest and only one partition is in use, otherwise StandardFacetsAccumulator.
protected FacetResultsHandler	createFacetResultsHandler(FacetRequest fr) Creates a FacetResultsHandler that matches the given FacetRequest.
protected static FacetResult	emptyResult(int ordinal, FacetRequest fr) Returns an empty FacetResult.
FacetsAggregator	getAggregator() Returns the FacetsAggregator to use for aggregating the categories found in the result documents.
protected Set<CategoryListParams>	getCategoryLists()

Methods inherited from class java.lang.Object

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

Field Detail

taxonomyReader

public final TaxonomyReader taxonomyReader

indexReader

public final IndexReader indexReader

facetArrays

public final FacetArrays facetArrays

searchParams

public FacetSearchParams searchParams

Constructor Detail

FacetsAccumulator

public FacetsAccumulator(FacetSearchParams searchParams,
                 IndexReader indexReader,
                 TaxonomyReader taxonomyReader)

Initializes the accumulator with the given search params, index reader and taxonomy reader. This constructor creates the default FacetArrays, which do not support reuse. If you want to use ReusingFacetArrays, you should use the FacetsAccumulator(FacetSearchParams, IndexReader, TaxonomyReader, FacetArrays) constructor.

FacetsAccumulator

public FacetsAccumulator(FacetSearchParams searchParams,
                 IndexReader indexReader,
                 TaxonomyReader taxonomyReader,
                 FacetArrays facetArrays)

Initializes the accumulator with the given parameters as well as FacetArrays. Note that the accumulator doesn't call FacetArrays.free(). If you require that (only makes sense if you use ReusingFacetArrays, you should do it after you've finished with the accumulator.

Method Detail

create

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

Creates an appropriate FacetsAccumulator, returning FacetsAccumulator when all requests are CountFacetRequest and only one partition is in use, otherwise StandardFacetsAccumulator.

emptyResult

protected static FacetResult emptyResult(int ordinal,
                      FacetRequest fr)

Returns an empty FacetResult.

getAggregator

public FacetsAggregator getAggregator()

Returns the FacetsAggregator to use for aggregating the categories found in the result documents. The default implementation returns CountingFacetsAggregator, or FastCountingFacetsAggregator if all categories can be decoded with DGapVInt8IntDecoder.

createFacetResultsHandler

protected FacetResultsHandler createFacetResultsHandler(FacetRequest fr)

Creates a FacetResultsHandler that matches the given FacetRequest.

getCategoryLists

protected Set<CategoryListParams> getCategoryLists()

accumulate

public List<FacetResult> accumulate(List<FacetsCollector.MatchingDocs> matchingDocs)
                             throws IOException

Used by FacetsCollector to build the list of facet results that match the facet requests that were given in the constructor.

Parameters:

matchingDocs - the documents that matched the query, per-segment.

Throws:

IOException