org.apache.lucene.index.sorter

Class BlockJoinSorter

java.lang.Object

org.apache.lucene.index.sorter.Sorter

org.apache.lucene.index.sorter.BlockJoinSorter

public abstract class BlockJoinSorter
extends Sorter

Helper class to sort readers that contain blocks of documents.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.index.sorter.Sorter

Sorter.DocComparator, Sorter.DocMap

Field Summary

Fields

Modifier and Type	Field and Description
protected Filter	parentsFilter

Fields inherited from class org.apache.lucene.index.sorter.Sorter

INDEX_ORDER_COMPARATOR, REVERSE_DOCS

Constructor Summary

Constructors

Constructor and Description
BlockJoinSorter(Filter parentsFilter) Sole constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected Sorter.DocComparator	getChildComparator(AtomicReader reader) Return a Sorter.DocComparator instance that will be called on children of the same parent.
protected abstract Sorter.DocComparator	getParentComparator(AtomicReader reader) Return a Sorter.DocComparator instance that will be called on parent doc IDs.
Sorter.DocMap	sort(AtomicReader reader) Returns a mapping from the old document ID to its new location in the sorted index.

Methods inherited from class org.apache.lucene.index.sorter.Sorter

getID, sort, toString

Methods inherited from class java.lang.Object

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

Field Detail

parentsFilter

protected final Filter parentsFilter

Constructor Detail

BlockJoinSorter

public BlockJoinSorter(Filter parentsFilter)

Sole constructor.

Method Detail

getParentComparator

protected abstract Sorter.DocComparator getParentComparator(AtomicReader reader)

Return a Sorter.DocComparator instance that will be called on parent doc IDs.

getChildComparator

protected Sorter.DocComparator getChildComparator(AtomicReader reader)

Return a Sorter.DocComparator instance that will be called on children of the same parent. By default, children of the same parent are not reordered.

sort

public final Sorter.DocMap sort(AtomicReader reader)
                         throws IOException

Description copied from class: Sorter

Returns a mapping from the old document ID to its new location in the sorted index. Implementations can use the auxiliary Sorter.sort(int, DocComparator) to compute the old-to-new permutation given a list of documents and their corresponding values.

A return value of null is allowed and means that reader is already sorted.

NOTE: deleted documents are expected to appear in the mapping as well, they will however be marked as deleted in the sorted view.

Specified by:

sort in class Sorter

Throws:

IOException