# Uses of Package
org.apache.lucene.util

Packages that use org.apache.lucene.util
Package
Description
org.apache.lucene.analysis
Text analysis.
org.apache.lucene.analysis.standard
Fast, general-purpose grammar-based tokenizer `StandardTokenizer` implements the Word Break rules from the Unicode Text Segmentation algorithm, as specified in Unicode Standard Annex #29.
org.apache.lucene.analysis.tokenattributes
General-purpose attributes for text analysis.
org.apache.lucene.codecs
Codecs API: API for customization of the encoding and structure of the index.
org.apache.lucene.codecs.compressing
Compressing helper classes.
org.apache.lucene.codecs.hnsw
HNSW vector helper classes.
org.apache.lucene.codecs.lucene102
Lucene 10.2 file format.
org.apache.lucene.codecs.lucene103
Lucene 10.3 file format.
org.apache.lucene.codecs.lucene103.blocktree
BlockTree terms dictionary.
org.apache.lucene.codecs.lucene90
Lucene 9.0 file format.
org.apache.lucene.codecs.lucene90.compressing
Lucene 9.0 compressing format.
org.apache.lucene.codecs.lucene95
Lucene 9.5 file format.
org.apache.lucene.codecs.lucene99
Lucene 9.9 file format.
org.apache.lucene.codecs.perfield
Postings format that can delegate to different formats per-field.
org.apache.lucene.document
The logical representation of a `Document` for indexing and searching.
org.apache.lucene.index
Code to maintain and access indices.
org.apache.lucene.internal.hppc
Internal copy of a subset of classes from the HPPC library.
org.apache.lucene.search
Code to search indices.
org.apache.lucene.search.comparators
Comparators, used to compare hits so as to determine their sort order when collecting the top results with `TopFieldCollector`.
org.apache.lucene.store
Binary i/o API, used for all index data.
org.apache.lucene.util
Some utility classes.
org.apache.lucene.util.automaton
Finite-state automaton for regular expressions.
org.apache.lucene.util.bkd
Block KD-tree, implementing the generic spatial data structure described in this paper.
org.apache.lucene.util.fst
Finite state transducers
org.apache.lucene.util.graph
Utility classes for working with token streams as graphs.
org.apache.lucene.util.hnsw
Navigable Small-World graph, nominally Hierarchical but currently only has a single layer.
org.apache.lucene.util.mutable
Comparable object wrappers
org.apache.lucene.util.packed
Packed integer arrays and streams.
org.apache.lucene.util.quantization
Provides quantization methods for scaling vector values to smaller data types and possibly fewer dimensions

- Classes in org.apache.lucene.util used by org.apache.lucene.analysis
  Class
  Description
  AttributeFactory
  An AttributeFactory creates instances of `AttributeImpl`s.
  AttributeSource
  An AttributeSource contains a list of different `AttributeImpl`s, and methods to add and get them.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  IgnoreRandomChains
  Annotation to not test a class or constructor with `TestRandomChains` integration test.
  ResourceLoader
  Abstraction for loading resources (streams, files, and classes).
  Unwrappable
  An object with this interface is a wrapper around another object (e.g., a filter with a delegate).
  Version
  Use by certain classes to match version compatibility across releases of Lucene.
- Classes in org.apache.lucene.util used by org.apache.lucene.analysis.standard
  Class
  Description
  AttributeFactory
  An AttributeFactory creates instances of `AttributeImpl`s.
  AttributeSource
  An AttributeSource contains a list of different `AttributeImpl`s, and methods to add and get them.
- Classes in org.apache.lucene.util used by org.apache.lucene.analysis.tokenattributes
  Class
  Description
  Attribute
  Base interface for attributes.
  AttributeImpl
  Base class for Attributes that can be added to a `AttributeSource`.
  AttributeReflector
  This interface is used to reflect contents of `AttributeSource` or `AttributeImpl`.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  BytesRefBuilder
  A builder for `BytesRef` instances.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  Bits
  Interface for Bitset-like structures.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  FixedBitSet
  BitSet of fixed length (numBits), backed by accessible (`FixedBitSet.getBits()`) long[], accessed with an int index, implementing `Bits` and `DocIdSet`.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.compressing
  Class
  Description
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.hnsw
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.lucene102
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.lucene103
  Class
  Description
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.lucene103.blocktree
  Class
  Description
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.lucene90
  Class
  Description
  Bits
  Interface for Bitset-like structures.
  FixedBitSet
  BitSet of fixed length (numBits), backed by accessible (`FixedBitSet.getBits()`) long[], accessed with an int index, implementing `Bits` and `DocIdSet`.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.lucene90.compressing
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.lucene95
  Class
  Description
  Bits
  Interface for Bitset-like structures.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.lucene99
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  Bits
  Interface for Bitset-like structures.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
- Classes in org.apache.lucene.util used by org.apache.lucene.codecs.perfield
  Class
  Description
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
- Classes in org.apache.lucene.util used by org.apache.lucene.document
  Class
  Description
  ArrayUtil.ByteArrayComparator
  Comparator for a fixed number of bytes.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
- Classes in org.apache.lucene.util used by org.apache.lucene.index
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  AttributeSource
  An AttributeSource contains a list of different `AttributeImpl`s, and methods to add and get them.
  Bits
  Interface for Bitset-like structures.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  BytesRefBuilder
  A builder for `BytesRef` instances.
  BytesRefIterator
  A simple iterator interface for `BytesRef` iteration.
  FixedBitSet
  BitSet of fixed length (numBits), backed by accessible (`FixedBitSet.getBits()`) long[], accessed with an int index, implementing `Bits` and `DocIdSet`.
  InfoStream
  Debugging API for Lucene classes such as `IndexWriter` and `SegmentInfos`.
  IntsRef
  Represents int[], as a slice (offset + length) into an existing int[].
  IOBooleanSupplier
  Boolean supplier that is allowed to throw an IOException.
  IOSupplier
  This is a result supplier that is allowed to throw an IOException.
  LongValues
  Abstraction over an array of longs.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
  SuppressForbidden
  Annotation to suppress forbidden-apis errors inside a whole class, a method, or a field.
  Unwrappable
  An object with this interface is a wrapper around another object (e.g., a filter with a delegate).
  Version
  Use by certain classes to match version compatibility across releases of Lucene.
- Classes in org.apache.lucene.util used by org.apache.lucene.internal.hppc
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
- Classes in org.apache.lucene.util used by org.apache.lucene.search
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  Attribute
  Base interface for attributes.
  AttributeImpl
  Base class for Attributes that can be added to a `AttributeSource`.
  AttributeReflector
  This interface is used to reflect contents of `AttributeSource` or `AttributeImpl`.
  AttributeSource
  An AttributeSource contains a list of different `AttributeImpl`s, and methods to add and get them.
  Bits
  Interface for Bitset-like structures.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  BytesRefIterator
  A simple iterator interface for `BytesRef` iteration.
  FixedBitSet
  BitSet of fixed length (numBits), backed by accessible (`FixedBitSet.getBits()`) long[], accessed with an int index, implementing `Bits` and `DocIdSet`.
  IOBooleanSupplier
  Boolean supplier that is allowed to throw an IOException.
  IOSupplier
  This is a result supplier that is allowed to throw an IOException.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
  PriorityQueue
  A priority queue maintains a partial ordering of its elements such that the least element can always be found in constant time.
  Unwrappable
  An object with this interface is a wrapper around another object (e.g., a filter with a delegate).
- Classes in org.apache.lucene.util used by org.apache.lucene.search.comparators
  Class
  Description
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
- Classes in org.apache.lucene.util used by org.apache.lucene.store
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  SuppressForbidden
  Annotation to suppress forbidden-apis errors inside a whole class, a method, or a field.
- Classes in org.apache.lucene.util used by org.apache.lucene.util
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  ArrayUtil.ByteArrayComparator
  Comparator for a fixed number of bytes.
  Attribute
  Base interface for attributes.
  AttributeFactory
  An AttributeFactory creates instances of `AttributeImpl`s.
  AttributeImpl
  Base class for Attributes that can be added to a `AttributeSource`.
  AttributeReflector
  This interface is used to reflect contents of `AttributeSource` or `AttributeImpl`.
  AttributeSource
  An AttributeSource contains a list of different `AttributeImpl`s, and methods to add and get them.
  AttributeSource.State
  This class holds the state of an AttributeSource.
  Bits
  Interface for Bitset-like structures.
  BitSet
  Base implementation for a bit set.
  ByteBlockPool
  This class enables the allocation of fixed-size buffers and their management as part of a buffer array.
  ByteBlockPool.Allocator
  Abstract class for allocating and freeing byte blocks.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  BytesRefArray.IndexedBytesRefIterator
  An extension of `BytesRefIterator` that allows retrieving the index of the current element
  BytesRefArray.SortState
  Used to iterate the elements of an array in a given order.
  BytesRefBuilder
  A builder for `BytesRef` instances.
  BytesRefComparator
  Specialized `BytesRef` comparator that `StringSorter` has optimizations for.
  BytesRefHash.BytesStartArray
  Manages allocation of the per-term addresses.
  BytesRefIterator
  A simple iterator interface for `BytesRef` iteration.
  CharsRef
  Represents char[], as a slice (offset + length) into an existing char[].
  CharsRefBuilder
  A builder for `CharsRef` instances.
  Counter
  Simple counter class
  DocIdSetBuilder.BulkAdder
  Utility class to efficiently add many docs in one go.
  FileDeleter.MsgType
  Types of messages this file deleter will broadcast REF: messages about reference FILE: messages about file
  FixedBitSet
  BitSet of fixed length (numBits), backed by accessible (`FixedBitSet.getBits()`) long[], accessed with an int index, implementing `Bits` and `DocIdSet`.
  GroupVIntUtil.IntReader
  Deprecated.
  No longer used.
  InfoStream
  Debugging API for Lucene classes such as `IndexWriter` and `SegmentInfos`.
  IntBlockPool.Allocator
  Abstract class for allocating and freeing int blocks.
  IntsRef
  Represents int[], as a slice (offset + length) into an existing int[].
  IOConsumer
  An IO operation with a single input that may throw an IOException.
  LongBitSet
  BitSet of fixed length (numBits), backed by accessible (`LongBitSet.getBits()`) long[], accessed with a long index.
  LongHeap
  A min heap that stores longs; a primitive priority queue that like all priority queues maintains a partial ordering of its elements such that the least element can always be found in constant time.
  LongsRef
  Represents long[], as a slice (offset + length) into an existing long[].
  LongValues
  Abstraction over an array of longs.
  MSBRadixSorter
  Radix sorter for variable-length strings.
  NamedSPILoader.NamedSPI
  Interface to support `NamedSPILoader.lookup(String)` by name.
  OfflineSorter.BufferSize
  A bit more descriptive unit for constructors.
  OfflineSorter.ByteSequencesReader
  Utility class to read length-prefixed byte[] entries from an input.
  OfflineSorter.ByteSequencesWriter
  Utility class to emit length-prefixed byte[] entries to an output stream for sorting.
  PagedBytes.PagedBytesDataInput
  Input that transparently iterates over pages
  PagedBytes.PagedBytesDataOutput
  Output that transparently spills to new pages as necessary
  PagedBytes.Reader
  Provides methods to read BytesRefs from a frozen PagedBytes.
  QueryBuilder.TermAndBoost
  Wraps a term and boost
  ResourceLoader
  Abstraction for loading resources (streams, files, and classes).
  RoaringDocIdSet
  `DocIdSet` implementation inspired from http://roaringbitmap.org/
  RoaringDocIdSet.Builder
  A builder of `RoaringDocIdSet`s.
  RollingBuffer.Resettable
  Implement to reset an instance
  Selector
  An implementation of a selection algorithm, ie.
  Sorter
  Base class for sorting algorithms implementations.
  SparseFixedBitSet
  A bit set that only stores longs that have at least one bit which is set.
  SuppressForbidden
  Annotation to suppress forbidden-apis errors inside a whole class, a method, or a field.
  TermAndVector
  Word2Vec unit composed by a term with the associated vector
  UnicodeUtil.UTF8CodePoint
  Holds a codepoint along with the number of bytes required to represent it in UTF8
  Version
  Use by certain classes to match version compatibility across releases of Lucene.
  VirtualMethod
  A utility for keeping backwards compatibility on previously abstract methods (or similar replacements).
  WeakIdentityMap
  Implements a combination of `WeakHashMap` and `IdentityHashMap`.
- Classes in org.apache.lucene.util used by org.apache.lucene.util.automaton
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  BytesRefBuilder
  A builder for `BytesRef` instances.
  BytesRefIterator
  A simple iterator interface for `BytesRef` iteration.
  IntsRef
  Represents int[], as a slice (offset + length) into an existing int[].
- Classes in org.apache.lucene.util used by org.apache.lucene.util.bkd
  Class
  Description
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  FixedBitSet
  BitSet of fixed length (numBits), backed by accessible (`FixedBitSet.getBits()`) long[], accessed with an int index, implementing `Bits` and `DocIdSet`.
  IORunnable
  A Runnable that may throw an IOException
- Classes in org.apache.lucene.util used by org.apache.lucene.util.fst
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  BytesRef
  Represents byte[], as a slice (offset + length) into an existing byte[].
  BytesRefBuilder
  A builder for `BytesRef` instances.
  CharsRef
  Represents char[], as a slice (offset + length) into an existing char[].
  IntsRef
  Represents int[], as a slice (offset + length) into an existing int[].
  IntsRefBuilder
  A builder for `IntsRef` instances.
- Classes in org.apache.lucene.util used by org.apache.lucene.util.graph
  Class
  Description
  AttributeSource
  An AttributeSource contains a list of different `AttributeImpl`s, and methods to add and get them.
- Classes in org.apache.lucene.util used by org.apache.lucene.util.hnsw
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  Bits
  Interface for Bitset-like structures.
  BitSet
  Base implementation for a bit set.
  InfoStream
  Debugging API for Lucene classes such as `IndexWriter` and `SegmentInfos`.
- Classes in org.apache.lucene.util used by org.apache.lucene.util.mutable
  Class
  Description
  BytesRefBuilder
  A builder for `BytesRef` instances.
- Classes in org.apache.lucene.util used by org.apache.lucene.util.packed
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.
  LongsRef
  Represents long[], as a slice (offset + length) into an existing long[].
  LongValues
  Abstraction over an array of longs.
- Classes in org.apache.lucene.util used by org.apache.lucene.util.quantization
  Class
  Description
  Accountable
  An object whose RAM usage can be computed.