Package org.apache.lucene.backward_codecs.lucene91

Class Lucene91HnswVectorsReader

java.lang.Object

org.apache.lucene.codecs.KnnVectorsReader

org.apache.lucene.backward_codecs.lucene91.Lucene91HnswVectorsReader

All Implemented Interfaces:

Closeable, AutoCloseable, Accountable

public final class Lucene91HnswVectorsReader
extends KnnVectorsReader

Reads vectors from the index segments along with index data structures supporting KNN search.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	Lucene91HnswVectorsReader.FieldEntry
private static final class	Lucene91HnswVectorsReader.OffHeapHnswGraph	Read the nearest-neighbors graph from the index input
(package private) static class	Lucene91HnswVectorsReader.OffHeapVectorValues	Read the vector values from the index input.

Field Summary

Fields

Modifier and Type	Field	Description
private final FieldInfos	fieldInfos
private final Map<String,Lucene91HnswVectorsReader.FieldEntry>	fields
private final IndexInput	vectorData
private final IndexInput	vectorIndex

Fields inherited from interface org.apache.lucene.util.Accountable

NULL_ACCOUNTABLE

Constructor Summary

Constructors

Constructor	Description
Lucene91HnswVectorsReader(SegmentReadState state)

Method Summary

Modifier and Type	Method	Description
void	checkIntegrity()	Checks consistency of this reader.
void	close()
private Bits	getAcceptOrds(Bits acceptDocs, Lucene91HnswVectorsReader.FieldEntry fieldEntry)
HnswGraph	getGraph(String field)	Get knn graph values; used for testing
private HnswGraph	getGraph(Lucene91HnswVectorsReader.FieldEntry entry)
private Lucene91HnswVectorsReader.OffHeapVectorValues	getOffHeapVectorValues(Lucene91HnswVectorsReader.FieldEntry fieldEntry)
VectorValues	getVectorValues(String field)	Returns the VectorValues for the given field.
private static IndexInput	openDataInput(SegmentReadState state, int versionMeta, String fileExtension, String codecName)
long	ramBytesUsed()	Return the memory usage of this object in bytes.
private Lucene91HnswVectorsReader.FieldEntry	readField(DataInput input)
private void	readFields(ChecksumIndexInput meta, FieldInfos infos)
private int	readMetadata(SegmentReadState state)
private VectorSimilarityFunction	readSimilarityFunction(DataInput input)
TopDocs	search(String field, float[] target, int k, Bits acceptDocs, int visitedLimit)	Return the k nearest neighbor documents as determined by comparison of their vector values for this field, to the given vector, by the field's similarity function.
private void	validateFieldEntry(FieldInfo info, Lucene91HnswVectorsReader.FieldEntry fieldEntry)

Methods inherited from class org.apache.lucene.codecs.KnnVectorsReader

getMergeInstance

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.lucene.util.Accountable

getChildResources

Field Details

fieldInfos

private final FieldInfos fieldInfos

fields

private final Map<String,Lucene91HnswVectorsReader.FieldEntry> fields

vectorData

private final IndexInput vectorData

vectorIndex

private final IndexInput vectorIndex

Constructor Details

Lucene91HnswVectorsReader

Lucene91HnswVectorsReader(SegmentReadState state)
                   throws IOException

Throws:

IOException

Method Details

readMetadata

private int readMetadata(SegmentReadState state)
                  throws IOException

Throws:

IOException

openDataInput

private static IndexInput openDataInput(SegmentReadState state,
 int versionMeta,
 String fileExtension,
 String codecName)
                                 throws IOException

Throws:

IOException

readFields

private void readFields(ChecksumIndexInput meta,
 FieldInfos infos)
                 throws IOException

Throws:

IOException

validateFieldEntry

private void validateFieldEntry(FieldInfo info,
 Lucene91HnswVectorsReader.FieldEntry fieldEntry)

readSimilarityFunction

private VectorSimilarityFunction readSimilarityFunction(DataInput input)
                                                 throws IOException

Throws:

IOException

readField

private Lucene91HnswVectorsReader.FieldEntry readField(DataInput input)
                                                throws IOException

Throws:

IOException

ramBytesUsed

public long ramBytesUsed()

Description copied from interface: Accountable

Return the memory usage of this object in bytes. Negative values are illegal.

checkIntegrity

public void checkIntegrity()
                    throws IOException

Description copied from class: KnnVectorsReader

Checks consistency of this reader.

Note that this may be costly in terms of I/O, e.g. may involve computing a checksum value against large data files.

Specified by:

checkIntegrity in class KnnVectorsReader

Throws:

IOException

getVectorValues

public VectorValues getVectorValues(String field)
                             throws IOException

Description copied from class: KnnVectorsReader

Returns the VectorValues for the given field. The behavior is undefined if the given field doesn't have KNN vectors enabled on its FieldInfo. The return value is never null.

Specified by:

getVectorValues in class KnnVectorsReader

Throws:

IOException

search

public TopDocs search(String field,
 float[] target,
 int k,
 Bits acceptDocs,
 int visitedLimit)
               throws IOException

Description copied from class: KnnVectorsReader

Return the k nearest neighbor documents as determined by comparison of their vector values for this field, to the given vector, by the field's similarity function. The score of each document is derived from the vector similarity in a way that ensures scores are positive and that a larger score corresponds to a higher ranking.

The search is allowed to be approximate, meaning the results are not guaranteed to be the true k closest neighbors. For large values of k (for example when k is close to the total number of documents), the search may also retrieve fewer than k documents.

The returned TopDocs will contain a ScoreDoc for each nearest neighbor, in order of their similarity to the query vector (decreasing scores). The TotalHits contains the number of documents visited during the search. If the search stopped early because it hit visitedLimit, it is indicated through the relation TotalHits.Relation.GREATER_THAN_OR_EQUAL_TO.

The behavior is undefined if the given field doesn't have KNN vectors enabled on its FieldInfo. The return value is never null.

Specified by:

search in class KnnVectorsReader

Parameters:

field - the vector field to search

target - the vector-valued query

k - the number of docs to return

acceptDocs - Bits that represents the allowed documents to match, or null if they are all allowed to match.

visitedLimit - the maximum number of nodes that the search is allowed to visit

Returns:

the k nearest neighbor documents, along with their (searchStrategy-specific) scores.

Throws:

IOException

getOffHeapVectorValues

private Lucene91HnswVectorsReader.OffHeapVectorValues getOffHeapVectorValues(Lucene91HnswVectorsReader.FieldEntry fieldEntry)
                                                                      throws IOException

Throws:

IOException

getAcceptOrds

private Bits getAcceptOrds(Bits acceptDocs,
 Lucene91HnswVectorsReader.FieldEntry fieldEntry)

getGraph

public HnswGraph getGraph(String field)
                   throws IOException

Get knn graph values; used for testing

Throws:

IOException

getGraph

private HnswGraph getGraph(Lucene91HnswVectorsReader.FieldEntry entry)
                    throws IOException

Throws:

IOException

close

public void close()
           throws IOException

Throws:

IOException