org.apache.lucene.search.grouping
Class TermAllGroupHeadsCollector<GH extends AbstractAllGroupHeadsCollector.GroupHead>

java.lang.Object
  org.apache.lucene.search.Collector
      org.apache.lucene.search.grouping.AbstractAllGroupHeadsCollector<GH>
          org.apache.lucene.search.grouping.TermAllGroupHeadsCollector<GH>

public abstract class TermAllGroupHeadsCollector<GH extends AbstractAllGroupHeadsCollector.GroupHead>
extends AbstractAllGroupHeadsCollector<GH>

A base implementation of AbstractAllGroupHeadsCollector for retrieving the most relevant groups when grouping on a string based group field. More specifically this all concrete implementations of this base implementation use FieldCache.StringIndex.

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

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.search.grouping.AbstractAllGroupHeadsCollector

AbstractAllGroupHeadsCollector.GroupHead<GROUP_VALUE_TYPE>, AbstractAllGroupHeadsCollector.TemporalResult

Field Summary

Fields inherited from class org.apache.lucene.search.grouping.AbstractAllGroupHeadsCollector

compIDXEnd, reversed, temporalResult

Constructor Summary

protected

TermAllGroupHeadsCollector(String groupField, int numberOfSorts)

Method Summary

static AbstractAllGroupHeadsCollector	create(String groupField, Sort sortWithinGroup) Creates an AbstractAllGroupHeadsCollector instance based on the supplied arguments.
static AbstractAllGroupHeadsCollector	create(String groupField, Sort sortWithinGroup, int initialSize) Creates an AbstractAllGroupHeadsCollector instance based on the supplied arguments.

Methods inherited from class org.apache.lucene.search.grouping.AbstractAllGroupHeadsCollector

acceptsDocsOutOfOrder, collect, getCollectedGroupHeads, groupHeadsSize, retrieveGroupHeadAndAddIfNotExist, retrieveGroupHeads, retrieveGroupHeads

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

setNextReader, setScorer

Methods inherited from class java.lang.Object

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

Constructor Detail

TermAllGroupHeadsCollector

protected TermAllGroupHeadsCollector(String groupField,
                                     int numberOfSorts)

Method Detail

create

public static AbstractAllGroupHeadsCollector create(String groupField,
                                                    Sort sortWithinGroup)
                                             throws IOException

Creates an AbstractAllGroupHeadsCollector instance based on the supplied arguments. This factory method decides with implementation is best suited. Delegates to create(String, org.apache.lucene.search.Sort, int) with an initialSize of 128.

Parameters:

groupField - The field to group by

sortWithinGroup - The sort within each group

Returns:

an AbstractAllGroupHeadsCollector instance based on the supplied arguments

Throws:

IOException - If I/O related errors occur

create

public static AbstractAllGroupHeadsCollector create(String groupField,
                                                    Sort sortWithinGroup,
                                                    int initialSize)
                                             throws IOException

Creates an AbstractAllGroupHeadsCollector instance based on the supplied arguments. This factory method decides with implementation is best suited.

Parameters:

groupField - The field to group by

sortWithinGroup - The sort within each group

initialSize - The initial allocation size of the internal int set and group list which should roughly match the total number of expected unique groups. Be aware that the heap usage is 4 bytes * initialSize.

Returns:

an AbstractAllGroupHeadsCollector instance based on the supplied arguments

Throws:

IOException - If I/O related errors occur