org.apache.lucene.search

Class BlockJoinComparatorSource

java.lang.Object

org.apache.lucene.search.FieldComparatorSource

org.apache.lucene.search.BlockJoinComparatorSource

public class BlockJoinComparatorSource
extends FieldComparatorSource

Helper class to sort readers that contain blocks of documents.

Note that this class is intended to used with SortingMergePolicy, and for other purposes has some limitations:

• Cannot yet be used with IndexSearcher.searchAfter
• Filling sort field values is not yet supported.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) Sort	childSort
(package private) Query	parentsFilter
(package private) Sort	parentSort

Constructor Summary

Constructors

Constructor and Description
BlockJoinComparatorSource(Query parentsFilter, Sort parentSort) Create a new BlockJoinComparatorSource, sorting only blocks of documents with parentSort and not reordering children with a block.
BlockJoinComparatorSource(Query parentsFilter, Sort parentSort, Sort childSort) Create a new BlockJoinComparatorSource, specifying the sort order for both blocks of documents and children within a block.

Method Summary

Modifier and Type	Method and Description
FieldComparator<java.lang.Integer>	newComparator(java.lang.String fieldname, int numHits, int sortPos, boolean reversed) Creates a comparator for the field in the given index.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

parentsFilter

final Query parentsFilter

parentSort

final Sort parentSort

childSort

final Sort childSort

Constructor Detail

BlockJoinComparatorSource

public BlockJoinComparatorSource(Query parentsFilter,
                                 Sort parentSort)

Create a new BlockJoinComparatorSource, sorting only blocks of documents with parentSort and not reordering children with a block.

Parameters:

parentsFilter - Filter identifying parent documents

parentSort - Sort for parent documents

BlockJoinComparatorSource

public BlockJoinComparatorSource(Query parentsFilter,
                                 Sort parentSort,
                                 Sort childSort)

Create a new BlockJoinComparatorSource, specifying the sort order for both blocks of documents and children within a block.

Parameters:

parentsFilter - Filter identifying parent documents

parentSort - Sort for parent documents

childSort - Sort for child documents in the same block

Method Detail

newComparator

public FieldComparator<java.lang.Integer> newComparator(java.lang.String fieldname,
                                                        int numHits,
                                                        int sortPos,
                                                        boolean reversed)
                                                 throws java.io.IOException

Description copied from class: FieldComparatorSource

Creates a comparator for the field in the given index.

Specified by:

newComparator in class FieldComparatorSource

Parameters:

fieldname - Name of the field to create comparator for.

Returns:

FieldComparator.

Throws:

java.io.IOException - If an error occurs reading the index.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object