Package org.apache.lucene.search.grouping

Class DistinctValuesCollectorManager<T,R>

java.lang.Object

org.apache.lucene.search.grouping.DistinctValuesCollectorManager<T,R>

All Implemented Interfaces:

CollectorManager<DistinctValuesCollector<T,R>,List<DistinctValuesCollector.GroupCount<T,R>>>

public class DistinctValuesCollectorManager<T,R>
extends Object
implements CollectorManager<DistinctValuesCollector<T,R>,List<DistinctValuesCollector.GroupCount<T,R>>>

A CollectorManager implementation for DistinctValuesCollector that supports parallel collection and merges results by taking the union of distinct values per group across segments.

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

Constructor Summary

Constructors

Constructor	Description
DistinctValuesCollectorManager(Supplier<GroupSelector<T>> groupSelectorFactory, Collection<SearchGroup<T>> searchGroups, Supplier<GroupSelector<R>> valueSelectorFactory)	Creates a new DistinctValuesCollectorManager.

Method Summary

Modifier and Type	Method	Description
DistinctValuesCollector<T,R>	newCollector()
List<DistinctValuesCollector.GroupCount<T,R>>	reduce(Collection<DistinctValuesCollector<T,R>> collectors)

Methods inherited from class java.lang.Object

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

Constructor Details

DistinctValuesCollectorManager

public DistinctValuesCollectorManager(Supplier<GroupSelector<T>> groupSelectorFactory,
 Collection<SearchGroup<T>> searchGroups,
 Supplier<GroupSelector<R>> valueSelectorFactory)

Creates a new DistinctValuesCollectorManager.

Parameters:

groupSelectorFactory - factory to create group selectors for each collector

searchGroups - the search groups from the first pass

valueSelectorFactory - factory to create value selectors for each collector

Method Details

newCollector

public DistinctValuesCollector<T,R> newCollector()
                                          throws IOException

Specified by:

newCollector in interface CollectorManager<T,R>

Throws:

IOException

reduce

public List<DistinctValuesCollector.GroupCount<T,R>> reduce(Collection<DistinctValuesCollector<T,R>> collectors)

Specified by:

reduce in interface CollectorManager<T,R>