Package org.apache.lucene.codecs.perfield

Class PerFieldKnnVectorsFormat.FieldsReader

java.lang.Object

org.apache.lucene.codecs.KnnVectorsReader

org.apache.lucene.codecs.perfield.PerFieldKnnVectorsFormat.FieldsReader

All Implemented Interfaces:

Closeable, AutoCloseable, Accountable

Enclosing class:

PerFieldKnnVectorsFormat

public static class PerFieldKnnVectorsFormat.FieldsReader
extends KnnVectorsReader

VectorReader that can wrap multiple delegate readers, selected by field.

Field Summary

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

NULL_ACCOUNTABLE

Constructor Summary

Constructors

Constructor	Description
FieldsReader(SegmentReadState readState)	Create a FieldsReader over a segment, opening VectorReaders for each KnnVectorsFormat specified by the indexed numeric vector fields.

Method Summary

Modifier and Type	Method	Description
void	checkIntegrity()	Checks consistency of this reader.
void	close()
KnnVectorsReader	getFieldReader(String field)	Return the underlying VectorReader for the given field
VectorValues	getVectorValues(String field)	Returns the VectorValues for the given field
long	ramBytesUsed()	Return the memory usage of this object in bytes.
TopDocs	search(String field, float[] target, int k, Bits acceptDocs)	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.

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

Constructor Detail

FieldsReader

public FieldsReader(SegmentReadState readState)
             throws IOException

Create a FieldsReader over a segment, opening VectorReaders for each KnnVectorsFormat specified by the indexed numeric vector fields.

Parameters:

readState - defines the fields

Throws:

IOException - if one of the delegate readers throws

Method Detail

getFieldReader

public KnnVectorsReader getFieldReader(String field)

Return the underlying VectorReader for the given field

Parameters:

field - the name of a numeric vector field

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

Specified by:

getVectorValues in class KnnVectorsReader

Throws:

IOException

search

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

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.

Returns:

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

Throws:

IOException

close

public void close()
           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.