Package org.apache.lucene.codecs.lucene90

Class Lucene90PointsFormat

java.lang.Object

org.apache.lucene.codecs.PointsFormat

org.apache.lucene.codecs.lucene90.Lucene90PointsFormat

public final class Lucene90PointsFormat
extends PointsFormat

Lucene 9.0 point format, which encodes dimensional values in a block KD-tree structure for fast 1D range and N dimensional shape intersection filtering. See this paper for details.

Data is stored across three files

• A .kdm file that records metadata about the fields, such as numbers of dimensions or numbers of bytes per dimension.
• A .kdi file that stores inner nodes of the tree.
• A .kdd file that stores leaf nodes, where most of the data lives.

See this wiki for detailed data structures of the three files.

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

Field Summary

Fields

Modifier and Type	Field	Description
static String	DATA_EXTENSION	Filename extension for the leaf blocks
static String	INDEX_EXTENSION	Filename extension for the index per field
static String	META_EXTENSION	Filename extension for the meta per field

Fields inherited from class org.apache.lucene.codecs.PointsFormat

EMPTY

Constructor Summary

Constructors

Constructor	Description
Lucene90PointsFormat()	Sole constructor

Method Summary

Modifier and Type	Method	Description
PointsReader	fieldsReader(SegmentReadState state)	Reads a segment.
PointsWriter	fieldsWriter(SegmentWriteState state)	Writes a new segment

Methods inherited from class java.lang.Object

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

Field Detail

DATA_EXTENSION

public static final String DATA_EXTENSION

Filename extension for the leaf blocks

See Also:

Constant Field Values

INDEX_EXTENSION

public static final String INDEX_EXTENSION

Filename extension for the index per field

See Also:

Constant Field Values

META_EXTENSION

public static final String META_EXTENSION

Filename extension for the meta per field

See Also:

Constant Field Values

Constructor Detail

Lucene90PointsFormat

public Lucene90PointsFormat()

Sole constructor

Method Detail

fieldsWriter

public PointsWriter fieldsWriter(SegmentWriteState state)
                          throws IOException

Description copied from class: PointsFormat

Writes a new segment

Specified by:

fieldsWriter in class PointsFormat

Throws:

IOException

fieldsReader

public PointsReader fieldsReader(SegmentReadState state)
                          throws IOException

Description copied from class: PointsFormat

Reads a segment. NOTE: by the time this call returns, it must hold open any files it will need to use; else, those files may be deleted. Additionally, required files may be deleted during the execution of this call before there is a chance to open them. Under these circumstances an IOException should be thrown by the implementation. IOExceptions are expected and will automatically cause a retry of the segment opening logic with the newly revised segments.

Specified by:

fieldsReader in class PointsFormat

Throws:

IOException