# Package org.apache.lucene.codecs.lucene99

package org.apache.lucene.codecs.lucene99
Lucene 9.9 file format.

- Related Packages
  Package
  Description
  org.apache.lucene.codecs
  Codecs API: API for customization of the encoding and structure of the index.
- Classes
  Class
  Description
  Lucene99FlatVectorsFormat
  Lucene 9.9 flat vector format, which encodes numeric vector values
  Lucene99FlatVectorsReader
  Reads vectors from the index segments.
  Lucene99FlatVectorsWriter
  Writes vector values to index segments.
  Lucene99HnswScalarQuantizedVectorsFormat
  Lucene 9.9 vector format, which encodes numeric vector values into an associated graph connecting the documents having values.
  Lucene99HnswVectorsFormat
  Lucene 9.9 vector format, which encodes numeric vector values into an associated graph connecting the documents having values.
  Lucene99HnswVectorsReader
  Reads vectors from the index segments along with index data structures supporting KNN search.
  Lucene99HnswVectorsWriter
  Writes vector values and knn graphs to index segments.
  Lucene99ScalarQuantizedVectorScorer
  Optimized scalar quantized implementation of `FlatVectorsScorer` for quantized vectors stored in the Lucene99 format.
  Lucene99ScalarQuantizedVectorsFormat
  Format supporting vector quantization, storage, and retrieval
  Lucene99ScalarQuantizedVectorsReader
  Reads Scalar Quantized vectors from the index segments along with index data structures.
  Lucene99ScalarQuantizedVectorsWriter
  Writes quantized vector values and metadata to index segments.
  Lucene99SegmentInfoFormat
  Lucene 9.9 Segment info format.
  OffHeapQuantizedByteVectorValues
  Read the quantized vector values and their score correction values from the index input.
  OffHeapQuantizedByteVectorValues.DenseOffHeapVectorValues
  Dense vector values that are stored off-heap.