Interface Summary
Interface Description

TaxonomyWriter
TaxonomyWriter is the interface which the faceted-search library uses to dynamically build the taxonomy at indexing time.

Interface Summary
Interface	Description
TaxonomyWriter	TaxonomyWriter is the interface which the faceted-search library uses to dynamically build the taxonomy at indexing time.

Class Summary
Class	Description
AssociationFacetField	Add an instance of this to your `Document` to add a facet label associated with an arbitrary byte[].
CachedOrdinalsReader	A per-segment cache of documents' facet ordinals.
CachedOrdinalsReader.CachedOrds	Holds the cached ordinals in two parallel `int[]` arrays.
CategoryPath	Holds a sequence of string components, specifying the hierarchical name of a category.
DocValuesOrdinalsReader	Decodes ordinals previously indexed into a BinaryDocValues field
FacetLabel	Holds a sequence of string components, specifying the hierarchical name of a category.
FastTaxonomyFacetCounts	Computes facets counts, assuming the default encoding into DocValues was used.
FloatAssociationFacetField	Add an instance of this to your `Document` to add a facet label associated with a float.
FloatTaxonomyFacets	Base class for all taxonomy-based facets that aggregate to a per-ords float[].
IntAssociationFacetField	Add an instance of this to your `Document` to add a facet label associated with an int.
IntTaxonomyFacets	Base class for all taxonomy-based facets that aggregate to a per-ords int[].
LRUHashMap<K,V>	LRUHashMap is an extension of Java's HashMap, which has a bounded size(); When it reaches that size, each time a new element is added, the least recently used (LRU) entry is removed.
OrdinalsReader	Provides per-document ordinals.
OrdinalsReader.OrdinalsSegmentReader	Returns ordinals for documents in one segment.
ParallelTaxonomyArrays	Returns 3 arrays for traversing the taxonomy: `parents`: `parents[i]` denotes the parent of category ordinal `i`. `children`: `children[i]` denotes a child of category ordinal `i`. `siblings`: `siblings[i]` denotes the sibling of category ordinal `i`. To traverse the taxonomy tree, you typically start with `children[0]` (ordinal 0 is reserved for ROOT), and then depends if you want to do DFS or BFS, you call `children[children[0]]` or `siblings[children[0]]` and so forth, respectively.
PrintTaxonomyStats	Prints how many ords are under each dimension.
SearcherTaxonomyManager	Manages near-real-time reopen of both an IndexSearcher and a TaxonomyReader.
SearcherTaxonomyManager.SearcherAndTaxonomy	Holds a matched pair of `IndexSearcher` and `TaxonomyReader`
TaxonomyFacetCounts	Reads from any `OrdinalsReader`; use `FastTaxonomyFacetCounts` if you are using the default encoding from `BinaryDocValues`.
TaxonomyFacets	Base class for all taxonomy-based facets impls.
TaxonomyFacetSumFloatAssociations	Aggregates sum of int values previously indexed with `FloatAssociationFacetField`, assuming the default encoding.
TaxonomyFacetSumIntAssociations	Aggregates sum of int values previously indexed with `IntAssociationFacetField`, assuming the default encoding.
TaxonomyFacetSumValueSource	Aggregates sum of values from `FunctionValues.doubleVal(int)`, for each facet label.
TaxonomyFacetSumValueSource.ScoreValueSource	`ValueSource` that returns the score for each hit; use this to aggregate the sum of all hit scores for each facet label.
TaxonomyReader	TaxonomyReader is the read-only interface with which the faceted-search library uses the taxonomy during search time.
TaxonomyReader.ChildrenIterator	An iterator over a category's children.

Package org.apache.lucene.facet.taxonomy Description

Taxonomy of Categories

Facets are defined using a hierarchy of categories, known as a Taxonomy. For example, the taxonomy of a book store application might have the following structure:

Author
- Mark Twain
- J. K. Rowling

Date
- 2010
  - March
  - April
- 2009

The Taxonomy translates category-paths into interger identifiers (often termed ordinals) and vice versa. The category Author/Mark Twain adds two nodes to the taxonomy: Author and Author/Mark Twain, each is assigned a different ordinal. The taxonomy maintains the invariant that a node always has an ordinal that is < all its children.