## Uses of Class
org.apache.lucene.util.BitSet

- Packages that use BitSet
  Package | Description
  --- | ---
  org.apache.lucene.util | Some utility classes.
  org.apache.lucene.util.hnsw | Navigable Small-World graph, nominally Hierarchical but currently only has a single layer.

- - ### Uses of BitSet in org.apache.lucene.util

    Subclasses of BitSet in org.apache.lucene.util
    Modifier and Type | Class | Description
    --- | --- | ---
    `class` | `FixedBitSet` | BitSet of fixed length (numBits), backed by accessible (`FixedBitSet.getBits()`) long[], accessed with an int index, implementing `Bits` and `DocIdSet`.
    `class` | `SparseFixedBitSet` | A bit set that only stores longs that have at least one bit which is set.

    Methods in org.apache.lucene.util that return BitSet
    Modifier and Type | Method | Description
    --- | --- | ---
    `BitSet` | BitDocIdSet.`bits()` |
    `BitSet` | BitSetIterator.`getBitSet()` | Return the wrapped `BitSet`.
    `static BitSet` | BitSet.`of​(DocIdSetIterator it, int maxDoc)` | Build a `BitSet` from the content of the provided `DocIdSetIterator`.

    Constructors in org.apache.lucene.util with parameters of type BitSet
    Constructor | Description
    --- | ---
    `BitDocIdSet​(BitSet set)` | Same as `BitDocIdSet(BitSet, long)` but uses the set's `approximate cardinality` as a cost.
    `BitDocIdSet​(BitSet set, long cost)` | Wrap the given `BitSet` as a `DocIdSet`.
    `BitSetIterator​(BitSet bits, long cost)` | Sole constructor.

  - ### Uses of BitSet in org.apache.lucene.util.hnsw

    Methods in org.apache.lucene.util.hnsw with parameters of type BitSet
    Modifier and Type | Method | Description
    --- | --- | ---
    `static InitializedHnswGraphBuilder` | InitializedHnswGraphBuilder.`fromGraph​(RandomVectorScorerSupplier scorerSupplier, int M, int beamWidth, long seed, HnswGraph initializerGraph, int[] newOrdMap, BitSet initializedNodes, int totalNumberOfVectors)` | Create a new HnswGraphBuilder that is initialized with the provided HnswGraph.
    `protected int[]` | IncrementalHnswGraphMerger.`getNewOrdMapping​(DocIdSetIterator mergedVectorIterator, BitSet initializedNodes)` | Creates a new mapping from old ordinals to new ordinals and returns the total number of vectors in the newly merged segment.

    Constructors in org.apache.lucene.util.hnsw with parameters of type BitSet
    Constructor | Description
    --- | ---
    `HnswConcurrentMergeBuilder​(TaskExecutor taskExecutor, int numWorker, RandomVectorScorerSupplier scorerSupplier, int M, int beamWidth, OnHeapHnswGraph hnsw, BitSet initializedNodes)` |
    `HnswGraphSearcher​(NeighborQueue candidates, BitSet visited)` | Creates a new graph searcher.
    `InitializedHnswGraphBuilder​(RandomVectorScorerSupplier scorerSupplier, int M, int beamWidth, long seed, OnHeapHnswGraph initializedGraph, BitSet initializedNodes)` |