# Uses of Package
org.apache.lucene.index

- Packages that use org.apache.lucene.index
  Package | Description
  --- | ---
  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.lucene90 | Lucene 9.0 file format.
  org.apache.lucene.codecs.lucene90.blocktree | BlockTree terms dictionary.
  org.apache.lucene.codecs.lucene90.compressing | Lucene 9.0 compressing format.
  org.apache.lucene.codecs.lucene94 | Lucene 9.4 file 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.geo | Geospatial Utility Implementations for Lucene Core
  org.apache.lucene.index | Code to maintain and access indices.
  org.apache.lucene.internal.tests | Internal bridges to package-private internals, for use by the lucene test framework only.
  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.search.knn | Classes related to vector search: knn and vector fields.
  org.apache.lucene.search.similarities | This package contains the various ranking models that can be used in Lucene.
  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.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.quantization | Provides quantization methods for scaling vector values to smaller data types and possibly fewer dimensions

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs
  Class | Description
  --- | ---
  BinaryDocValues | A per-document numeric value.
  ByteVectorValues | This class provides access to per-document floating point vector values indexed as `KnnByteVectorField`.
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  FieldInfos | Collection of `FieldInfo`s (accessible by number or by name).
  Fields | Provides a `Terms` index for fields that have it, and lists which fields do.
  FloatVectorValues | This class provides access to per-document floating point vector values indexed as `KnnFloatVectorField`.
  Impact | Per-document scoring factors.
  ImpactsEnum | Extension of `PostingsEnum` which also provides information about upcoming impacts.
  IndexOptions | Controls how much information is stored in the postings lists.
  MergeState | Holds common state used during segment merging.
  NumericDocValues | A per-document numeric value.
  OrdTermState | An ordinal based `TermState`
  PointValues | Access to indexed numeric values.
  PointValues.IntersectVisitor | We recurse the `PointValues.PointTree`, using a provided instance of this to guide the recursion.
  PointValues.PointTree | Basic operations to read the KD-tree.
  PostingsEnum | Iterates through the postings.
  SegmentCommitInfo | Embeds a [read-only] SegmentInfo and adds per-commit fields.
  SegmentInfo | Information about a segment such as its name, directory, and files related to the segment.
  SegmentReadState | Holder class for common parameters used during read.
  SegmentWriteState | Holder class for common parameters used during write.
  SortedDocValues | A per-document byte[] with presorted values.
  SortedNumericDocValues | A list of per-document numeric values, sorted according to `Long.compare(long, long)`.
  SortedSetDocValues | A multi-valued version of `SortedDocValues`.
  Sorter.DocMap | A permutation of doc IDs.
  StoredFields | API for reading stored fields.
  StoredFieldVisitor | Expert: provides a low-level means of accessing the stored field values in an index.
  StoredFieldVisitor.Status | Enumeration of possible return values for `StoredFieldVisitor.needsField(org.apache.lucene.index.FieldInfo)`.
  TermsEnum | Iterator to seek (`TermsEnum.seekCeil(BytesRef)`, `TermsEnum.seekExact(BytesRef)`) or step through (`BytesRefIterator.next()` terms to obtain frequency information (`TermsEnum.docFreq()`), `PostingsEnum` or `PostingsEnum` for the current term (`TermsEnum.postings(org.apache.lucene.index.PostingsEnum)`.
  TermState | Encapsulates all required internal state to position the associated `TermsEnum` without re-seeking.
  TermVectors | API for reading term vectors.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.compressing
  Class | Description
  --- | ---
  MergeState | Holds common state used during segment merging.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.lucene90
  Class | Description
  --- | ---
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  FieldInfos | Collection of `FieldInfo`s (accessible by number or by name).
  MergeState | Holds common state used during segment merging.
  PointValues | Access to indexed numeric values.
  SegmentCommitInfo | Embeds a [read-only] SegmentInfo and adds per-commit fields.
  SegmentInfo | Information about a segment such as its name, directory, and files related to the segment.
  SegmentReadState | Holder class for common parameters used during read.
  SegmentWriteState | Holder class for common parameters used during write.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.lucene90.blocktree
  Class | Description
  --- | ---
  Fields | Provides a `Terms` index for fields that have it, and lists which fields do.
  SegmentReadState | Holder class for common parameters used during read.
  SegmentWriteState | Holder class for common parameters used during write.
  Terms | Access to the terms in a specific field.
  TermsEnum | Iterator to seek (`TermsEnum.seekCeil(BytesRef)`, `TermsEnum.seekExact(BytesRef)`) or step through (`BytesRefIterator.next()` terms to obtain frequency information (`TermsEnum.docFreq()`), `PostingsEnum` or `PostingsEnum` for the current term (`TermsEnum.postings(org.apache.lucene.index.PostingsEnum)`.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.lucene90.compressing
  Class | Description
  --- | ---
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  FieldInfos | Collection of `FieldInfo`s (accessible by number or by name).
  Fields | Provides a `Terms` index for fields that have it, and lists which fields do.
  MergeState | Holds common state used during segment merging.
  SegmentInfo | Information about a segment such as its name, directory, and files related to the segment.
  StoredFields | API for reading stored fields.
  StoredFieldVisitor | Expert: provides a low-level means of accessing the stored field values in an index.
  TermVectors | API for reading term vectors.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.lucene94
  Class | Description
  --- | ---
  FieldInfos | Collection of `FieldInfo`s (accessible by number or by name).
  SegmentInfo | Information about a segment such as its name, directory, and files related to the segment.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.lucene95
  Class | Description
  --- | ---
  ByteVectorValues | This class provides access to per-document floating point vector values indexed as `KnnByteVectorField`.
  DocsWithFieldSet | Accumulator for documents that have a value for a field.
  FloatVectorValues | This class provides access to per-document floating point vector values indexed as `KnnFloatVectorField`.
  VectorEncoding | The numeric datatype of the vector values.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.lucene99
  Class | Description
  --- | ---
  ByteVectorValues | This class provides access to per-document floating point vector values indexed as `KnnByteVectorField`.
  DocsWithFieldSet | Accumulator for documents that have a value for a field.
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  FloatVectorValues | This class provides access to per-document floating point vector values indexed as `KnnFloatVectorField`.
  ImpactsEnum | Extension of `PostingsEnum` which also provides information about upcoming impacts.
  MergeState | Holds common state used during segment merging.
  NumericDocValues | A per-document numeric value.
  OrdTermState | An ordinal based `TermState`
  PostingsEnum | Iterates through the postings.
  SegmentInfo | Information about a segment such as its name, directory, and files related to the segment.
  SegmentReadState | Holder class for common parameters used during read.
  SegmentWriteState | Holder class for common parameters used during write.
  Sorter.DocMap | A permutation of doc IDs.
  TermState | Encapsulates all required internal state to position the associated `TermsEnum` without re-seeking.
  VectorEncoding | The numeric datatype of the vector values.
  VectorSimilarityFunction | Vector similarity function; used in search to return top K most similar vectors to a target vector.

- Classes in org.apache.lucene.index used by org.apache.lucene.codecs.perfield
  Class | Description
  --- | ---
  ByteVectorValues | This class provides access to per-document floating point vector values indexed as `KnnByteVectorField`.
  FloatVectorValues | This class provides access to per-document floating point vector values indexed as `KnnFloatVectorField`.
  SegmentReadState | Holder class for common parameters used during read.
  SegmentWriteState | Holder class for common parameters used during write.

- Classes in org.apache.lucene.index used by org.apache.lucene.document
  Class | Description
  --- | ---
  BinaryDocValues | A per-document numeric value.
  DocValuesType | DocValues types.
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  IndexableField | Represents a single field for indexing.
  IndexableFieldType | Describes the properties of a field.
  IndexOptions | Controls how much information is stored in the postings lists.
  StoredFieldVisitor | Expert: provides a low-level means of accessing the stored field values in an index.
  StoredFieldVisitor.Status | Enumeration of possible return values for `StoredFieldVisitor.needsField(org.apache.lucene.index.FieldInfo)`.
  VectorEncoding | The numeric datatype of the vector values.
  VectorSimilarityFunction | Vector similarity function; used in search to return top K most similar vectors to a target vector.

- Classes in org.apache.lucene.index used by org.apache.lucene.geo
  Class | Description
  --- | ---
  PointValues.Relation | Used by `PointValues.intersect(org.apache.lucene.index.PointValues.IntersectVisitor)` to check how each recursive cell corresponds to the query.

- Classes in org.apache.lucene.index used by org.apache.lucene.index
  Class | Description
  --- | ---
  BaseCompositeReader | Base class for implementing `CompositeReader`s based on an array of sub-readers.
  BaseTermsEnum | A base TermsEnum that adds default implementations for `BaseTermsEnum.attributes()` `BaseTermsEnum.termState()` `BaseTermsEnum.seekExact(BytesRef)` `BaseTermsEnum.seekExact(BytesRef, TermState)` In some cases, the default implementation may be slow and consume huge memory, so subclass SHOULD have its own implementation if possible.
  BinaryDocValues | A per-document numeric value.
  ByteVectorValues | This class provides access to per-document floating point vector values indexed as `KnnByteVectorField`.
  CheckIndex.Options | Run-time configuration options for CheckIndex commands.
  CheckIndex.Status | Returned from `CheckIndex.checkIndex()` detailing the health and status of the index.
  CheckIndex.Status.DocValuesStatus | Status from testing DocValues
  CheckIndex.Status.FieldInfoStatus | Status from testing field infos.
  CheckIndex.Status.FieldNormStatus | Status from testing field norms.
  CheckIndex.Status.IndexSortStatus | Status from testing index sort
  CheckIndex.Status.LiveDocStatus | Status from testing livedocs
  CheckIndex.Status.PointsStatus | Status from testing PointValues
  CheckIndex.Status.SegmentInfoStatus | Holds the status of each segment in the index.
  CheckIndex.Status.SoftDeletsStatus | Status from testing soft deletes
  CheckIndex.Status.StoredFieldStatus | Status from testing stored fields.
  CheckIndex.Status.TermIndexStatus | Status from testing term index.
  CheckIndex.Status.TermVectorStatus | Status from testing stored fields.
  CheckIndex.Status.VectorValuesStatus | Status from testing vector values
  CodecReader | LeafReader implemented by codec APIs.
  CompositeReader | Instances of this reader type can only be used to get stored fields from the underlying LeafReaders, but it is not possible to directly retrieve postings.
  CompositeReaderContext | `IndexReaderContext` for `CompositeReader` instance.
  ConcurrentMergeScheduler.MergeThread | Runs a merge thread to execute a single merge, then exits.
  DirectoryReader | DirectoryReader is an implementation of `CompositeReader` that can read indexes in a `Directory`.
  DocIDMerger | Utility class to help merging documents from sub-readers according to either simple concatenated (unsorted) order, or by a specified index-time sort, skipping deleted documents and remapping non-deleted documents.
  DocIDMerger.Sub | Represents one sub-reader being merged
  DocValuesType | DocValues types.
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  FieldInfos | Collection of `FieldInfo`s (accessible by number or by name).
  Fields | Provides a `Terms` index for fields that have it, and lists which fields do.
  FilterCodecReader | A `FilterCodecReader` contains another CodecReader, which it uses as its basic source of data, possibly transforming the data along the way or providing additional functionality.
  FilterDirectoryReader | A FilterDirectoryReader wraps another DirectoryReader, allowing implementations to transform or extend it.
  FilterDirectoryReader.SubReaderWrapper | Factory class passed to FilterDirectoryReader constructor that allows subclasses to wrap the filtered DirectoryReader's subreaders.
  FilteredTermsEnum | Abstract class for enumerating a subset of all terms.
  FilteredTermsEnum.AcceptStatus | Return value, if term should be accepted or the iteration should `END`.
  FilterLeafReader | A `FilterLeafReader` contains another LeafReader, which it uses as its basic source of data, possibly transforming the data along the way or providing additional functionality.
  FilterLeafReader.FilterFields | Base class for filtering `Fields` implementations.
  FilterLeafReader.FilterTerms | Base class for filtering `Terms` implementations.
  FilterLeafReader.FilterTermsEnum | Base class for filtering `TermsEnum` implementations.
  FilterMergePolicy | A wrapper for `MergePolicy` instances.
  FloatVectorValues | This class provides access to per-document floating point vector values indexed as `KnnFloatVectorField`.
  Impact | Per-document scoring factors.
  Impacts | Information about upcoming impacts, ie.
  ImpactsEnum | Extension of `PostingsEnum` which also provides information about upcoming impacts.
  ImpactsSource | Source of `Impacts`.
  IndexableField | Represents a single field for indexing.
  IndexableFieldType | Describes the properties of a field.
  IndexCommit | Expert: represents a single commit into an index as seen by the `IndexDeletionPolicy` or `IndexReader`.
  IndexDeletionPolicy | Expert: policy for deletion of stale `index commits`.
  IndexOptions | Controls how much information is stored in the postings lists.
  IndexReader | IndexReader is an abstract class, providing an interface for accessing a point-in-time view of an index.
  IndexReader.CacheHelper | A utility class that gives hooks in order to help build a cache based on the data that is contained in this index.
  IndexReader.CacheKey | A cache key identifying a resource that is being cached on.
  IndexReader.ClosedListener | A listener that is called when a resource gets closed.
  IndexReaderContext | A struct like class that represents a hierarchical relationship between `IndexReader` instances.
  IndexSorter | Handles how documents should be sorted in an index, both within a segment and between segments.
  IndexSorter.ComparableProvider | Used for sorting documents across segments
  IndexSorter.DocComparator | A comparator of doc IDs, used for sorting documents within a segment
  IndexSorter.NumericDocValuesProvider | Provide a NumericDocValues instance for a LeafReader
  IndexSorter.SortedDocValuesProvider | Provide a SortedDocValues instance for a LeafReader
  IndexWriter | An `IndexWriter` creates and maintains an index.
  IndexWriter.DocStats | DocStats for this index
  IndexWriter.IndexReaderWarmer | If `DirectoryReader.open(IndexWriter)` has been called (ie, this writer is in near real-time mode), then after a merge completes, this class can be invoked to warm the reader on the newly merged segment, before the merge commits.
  IndexWriterConfig | Holds all the configuration that is used to create an `IndexWriter`.
  IndexWriterConfig.OpenMode | Specifies the open mode for `IndexWriter`.
  IndexWriterEventListener | A callback event listener for recording key events happened inside IndexWriter
  LeafMetaData | Provides read-only metadata about a leaf.
  LeafReader | `LeafReader` is an abstract class, providing an interface for accessing an index.
  LeafReaderContext | `IndexReaderContext` for `LeafReader` instances.
  LiveIndexWriterConfig | Holds all the configuration used by `IndexWriter` with few setters for settings that can be changed on an `IndexWriter` instance "live".
  LogMergePolicy | This class implements a `MergePolicy` that tries to merge segments into levels of exponentially increasing size, where each level has fewer segments than the value of the merge factor.
  MergePolicy | Expert: a MergePolicy determines the sequence of primitive merge operations.
  MergePolicy.MergeAbortedException | Thrown when a merge was explicitly aborted because `IndexWriter.abortMerges()` was called.
  MergePolicy.MergeContext | This interface represents the current context of the merge selection process.
  MergePolicy.MergeSpecification | A MergeSpecification instance provides the information necessary to perform multiple merges.
  MergePolicy.OneMerge | OneMerge provides the information necessary to perform an individual primitive merge operation, resulting in a single new segment.
  MergePolicy.OneMergeProgress | Progress and state for an executing merge.
  MergePolicy.OneMergeProgress.PauseReason | Reason for pausing the merge thread.
  MergeScheduler | Expert: `IndexWriter` uses an instance implementing this interface to execute the merges selected by a `MergePolicy`.
  MergeScheduler.MergeSource | Provides access to new merges and executes the actual merge
  MergeState | Holds common state used during segment merging.
  MergeState.DocMap | A map of doc IDs.
  MergeTrigger | MergeTrigger is passed to `MergePolicy.findMerges(MergeTrigger, SegmentInfos, MergePolicy.MergeContext)` to indicate the event that triggered the merge.
  MultiFields | Provides a single `Fields` term index view over an `IndexReader`.
  MultiPostingsEnum | Exposes `PostingsEnum`, merged from `PostingsEnum` API of sub-segments.
  MultiPostingsEnum.EnumWithSlice | Holds a `PostingsEnum` along with the corresponding `ReaderSlice`.
  MultiTermsEnum | Exposes `TermsEnum` API, merged from `TermsEnum` API of sub-segments.
  NumericDocValues | A per-document numeric value.
  OneMergeWrappingMergePolicy | A wrapping merge policy that wraps the `MergePolicy.OneMerge` objects returned by the wrapped merge policy.
  OrdinalMap | Maps per-segment ordinals to/from global ordinal space, using a compact packed-ints representation.
  PointValues | Access to indexed numeric values.
  PointValues.IntersectVisitor | We recurse the `PointValues.PointTree`, using a provided instance of this to guide the recursion.
  PointValues.PointTree | Basic operations to read the KD-tree.
  PointValues.Relation | Used by `PointValues.intersect(org.apache.lucene.index.PointValues.IntersectVisitor)` to check how each recursive cell corresponds to the query.
  PostingsEnum | Iterates through the postings.
  PrefixCodedTerms | Prefix codes term instances (prefixes are shared).
  PrefixCodedTerms.TermIterator | An iterator over the list of terms stored in a `PrefixCodedTerms`.
  QueryTimeout | Query timeout abstraction that controls whether a query should continue or be stopped.
  ReaderSlice | Subreader slice from a parent composite reader.
  SegmentCommitInfo | Embeds a [read-only] SegmentInfo and adds per-commit fields.
  SegmentInfo | Information about a segment such as its name, directory, and files related to the segment.
  SegmentInfos | A collection of segmentInfo objects with methods for operating on those segments in relation to the file system.
  SegmentReadState | Holder class for common parameters used during read.
  SegmentWriteState | Holder class for common parameters used during write.
  SnapshotDeletionPolicy | An `IndexDeletionPolicy` that wraps any other `IndexDeletionPolicy` and adds the ability to hold and later release snapshots of an index.
  SortedDocValues | A per-document byte[] with presorted values.
  SortedNumericDocValues | A list of per-document numeric values, sorted according to `Long.compare(long, long)`.
  SortedSetDocValues | A multi-valued version of `SortedDocValues`.
  Sorter.DocMap | A permutation of doc IDs.
  SortFieldProvider | Reads/Writes a named SortField from a segment info file, used to record index sorts
  StoredFields | API for reading stored fields.
  StoredFieldVisitor | Expert: provides a low-level means of accessing the stored field values in an index.
  StoredFieldVisitor.Status | Enumeration of possible return values for `StoredFieldVisitor.needsField(org.apache.lucene.index.FieldInfo)`.
  Term | A Term represents a word from text.
  Terms | Access to the terms in a specific field.
  TermsEnum | Iterator to seek (`TermsEnum.seekCeil(BytesRef)`, `TermsEnum.seekExact(BytesRef)`) or step through (`BytesRefIterator.next()` terms to obtain frequency information (`TermsEnum.docFreq()`), `PostingsEnum` or `PostingsEnum` for the current term (`TermsEnum.postings(org.apache.lucene.index.PostingsEnum)`.
  TermsEnum.SeekStatus | Represents returned result from `TermsEnum.seekCeil(org.apache.lucene.util.BytesRef)`.
  TermState | Encapsulates all required internal state to position the associated `TermsEnum` without re-seeking.
  TermStates | Maintains a `IndexReader` `TermState` view over `IndexReader` instances containing a single term.
  TermVectors | API for reading term vectors.
  TieredMergePolicy | Merges segments of approximately equal size, subject to an allowed number of segments per tier.
  TieredMergePolicy.MergeScore | Holds score and explanation for a single candidate merge.
  TwoPhaseCommit | An interface for implementations that support 2-phase commit.
  TwoPhaseCommitTool.CommitFailException | Thrown by `TwoPhaseCommitTool.execute(TwoPhaseCommit...)` when an object fails to commit().
  TwoPhaseCommitTool.PrepareCommitFailException | Thrown by `TwoPhaseCommitTool.execute(TwoPhaseCommit...)` when an object fails to prepareCommit().
  VectorEncoding | The numeric datatype of the vector values.
  VectorSimilarityFunction | Vector similarity function; used in search to return top K most similar vectors to a target vector.
  VectorValues | Deprecated. use `FloatVectorValues` instead

- Classes in org.apache.lucene.index used by org.apache.lucene.internal.tests
  Class | Description
  --- | ---
  ConcurrentMergeScheduler | A `MergeScheduler` that runs each merge using a separate thread.
  DirectoryReader | DirectoryReader is an implementation of `CompositeReader` that can read indexes in a `Directory`.
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  FieldInfos | Collection of `FieldInfo`s (accessible by number or by name).
  Impacts | Information about upcoming impacts, ie.
  IndexReader.CacheKey | A cache key identifying a resource that is being cached on.
  IndexWriter | An `IndexWriter` creates and maintains an index.
  SegmentCommitInfo | Embeds a [read-only] SegmentInfo and adds per-commit fields.
  SegmentReader | IndexReader implementation over a single segment.

- Classes in org.apache.lucene.index used by org.apache.lucene.search
  Class | Description
  --- | ---
  BinaryDocValues | A per-document numeric value.
  DirectoryReader | DirectoryReader is an implementation of `CompositeReader` that can read indexes in a `Directory`.
  ImpactsEnum | Extension of `PostingsEnum` which also provides information about upcoming impacts.
  ImpactsSource | Source of `Impacts`.
  IndexReader | IndexReader is an abstract class, providing an interface for accessing a point-in-time view of an index.
  IndexReaderContext | A struct like class that represents a hierarchical relationship between `IndexReader` instances.
  IndexSorter | Handles how documents should be sorted in an index, both within a segment and between segments.
  IndexWriter | An `IndexWriter` creates and maintains an index.
  LeafReader | `LeafReader` is an abstract class, providing an interface for accessing an index.
  LeafReaderContext | `IndexReaderContext` for `LeafReader` instances.
  NumericDocValues | A per-document numeric value.
  PostingsEnum | Iterates through the postings.
  PrefixCodedTerms | Prefix codes term instances (prefixes are shared).
  QueryTimeout | Query timeout abstraction that controls whether a query should continue or be stopped.
  SortedDocValues | A per-document byte[] with presorted values.
  SortedNumericDocValues | A list of per-document numeric values, sorted according to `Long.compare(long, long)`.
  SortedSetDocValues | A multi-valued version of `SortedDocValues`.
  SortFieldProvider | Reads/Writes a named SortField from a segment info file, used to record index sorts
  StoredFields | API for reading stored fields.
  StoredFieldVisitor | Expert: provides a low-level means of accessing the stored field values in an index.
  Term | A Term represents a word from text.
  Terms | Access to the terms in a specific field.
  TermsEnum | Iterator to seek (`TermsEnum.seekCeil(BytesRef)`, `TermsEnum.seekExact(BytesRef)`) or step through (`BytesRefIterator.next()` terms to obtain frequency information (`TermsEnum.docFreq()`), `PostingsEnum` or `PostingsEnum` for the current term (`TermsEnum.postings(org.apache.lucene.index.PostingsEnum)`.
  TermsEnum.SeekStatus | Represents returned result from `TermsEnum.seekCeil(org.apache.lucene.util.BytesRef)`.
  TermState | Encapsulates all required internal state to position the associated `TermsEnum` without re-seeking.
  TermStates | Maintains a `IndexReader` `TermState` view over `IndexReader` instances containing a single term.

- Classes in org.apache.lucene.index used by org.apache.lucene.search.comparators
  Class | Description
  --- | ---
  LeafReaderContext | `IndexReaderContext` for `LeafReader` instances.
  NumericDocValues | A per-document numeric value.
  SortedDocValues | A per-document byte[] with presorted values.

- Classes in org.apache.lucene.index used by org.apache.lucene.search.knn
  Class | Description
  --- | ---
  LeafReaderContext | `IndexReaderContext` for `LeafReader` instances.

- Classes in org.apache.lucene.index used by org.apache.lucene.search.similarities
  Class | Description
  --- | ---
  FieldInvertState | This class tracks the number and position / offset parameters of terms being added to the index.

- Classes in org.apache.lucene.index used by org.apache.lucene.util
  Class | Description
  --- | ---
  PointValues | Access to indexed numeric values.
  Term | A Term represents a word from text.
  Terms | Access to the terms in a specific field.

- Classes in org.apache.lucene.index used by org.apache.lucene.util.automaton
  Class | Description
  --- | ---
  Terms | Access to the terms in a specific field.
  TermsEnum | Iterator to seek (`TermsEnum.seekCeil(BytesRef)`, `TermsEnum.seekExact(BytesRef)`) or step through (`BytesRefIterator.next()` terms to obtain frequency information (`TermsEnum.docFreq()`), `PostingsEnum` or `PostingsEnum` for the current term (`TermsEnum.postings(org.apache.lucene.index.PostingsEnum)`.

- Classes in org.apache.lucene.index used by org.apache.lucene.util.bkd
  Class | Description
  --- | ---
  MergeState.DocMap | A map of doc IDs.
  PointValues | Access to indexed numeric values.
  PointValues.PointTree | Basic operations to read the KD-tree.

- Classes in org.apache.lucene.index used by org.apache.lucene.util.graph
  Class | Description
  --- | ---
  Term | A Term represents a word from text.

- Classes in org.apache.lucene.index used by org.apache.lucene.util.hnsw
  Class | Description
  --- | ---
  FieldInfo | Access to the Field Info file that describes document fields and whether or not they are indexed.
  MergeState.DocMap | A map of doc IDs.
  VectorSimilarityFunction | Vector similarity function; used in search to return top K most similar vectors to a target vector.

- Classes in org.apache.lucene.index used by org.apache.lucene.util.quantization
  Class | Description
  --- | ---
  ByteVectorValues | This class provides access to per-document floating point vector values indexed as `KnnByteVectorField`.
  FloatVectorValues | This class provides access to per-document floating point vector values indexed as `KnnFloatVectorField`.
  VectorSimilarityFunction | Vector similarity function; used in search to return top K most similar vectors to a target vector.