Package org.apache.lucene.facet
Class StringValueFacetCounts
java.lang.Object
org.apache.lucene.facet.Facets
org.apache.lucene.facet.StringValueFacetCounts
Compute facet counts from a previously indexed
SortedSetDocValues
or SortedDocValues
field. This approach will execute facet counting against
the string values found in the specified field, with no assumptions on their format. Unlike
SortedSetDocValuesFacetCounts
, no assumption is made
about a "dimension" path component being indexed. Because of this, the field itself is
effectively treated as the "dimension", and counts for all unique string values are produced.
This approach is meant to complement LongValueFacetCounts
in that they both provide facet
counting on a doc value field with no assumptions of content.
This implementation is useful if you want to dynamically count against any string doc value
field without relying on FacetField
and FacetsConfig
. The disadvantage is that a
separate field is required for each "dimension". If you want to pack multiple dimensions into the
same doc values field, you probably want one of FastTaxonomyFacetCounts
or SortedSetDocValuesFacetCounts
.
Note that there is an added cost on every IndexReader
open to create a new StringDocValuesReaderState
. Also note that this class should be instantiated and used from a
single thread, because it holds a thread-private instance of SortedSetDocValues
.
- WARNING: This API is experimental and might change in incompatible ways in the next release.
-
Constructor Summary
ConstructorDescriptionReturns all facet counts for the field, same result as searching onMatchAllDocsQuery
but faster.StringValueFacetCounts
(StringDocValuesReaderState state, FacetsCollector facetsCollector) Counts facets across the provided hits. -
Method Summary
Modifier and TypeMethodDescriptiongetAllDims
(int topN) Returns topN labels for any dimension that had hits, sorted by the number of hits that dimension matched; this is used for "sparse" faceting, where many different dimensions were indexed, for example depending on the type of document.getSpecificValue
(String dim, String... path) Return the count or value for a specific path.getTopChildren
(int topN, String dim, String... path) Returns the topN child labels under the specified path.
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Constructor Details
-
StringValueFacetCounts
Returns all facet counts for the field, same result as searching onMatchAllDocsQuery
but faster.- Throws:
IOException
-
StringValueFacetCounts
public StringValueFacetCounts(StringDocValuesReaderState state, FacetsCollector facetsCollector) throws IOException Counts facets across the provided hits.- Throws:
IOException
-
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Method Details
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getTopChildren
Description copied from class:Facets
Returns the topN child labels under the specified path. Returns null if the specified path doesn't exist or if this dimension was never seen.- Specified by:
getTopChildren
in classFacets
- Throws:
IOException
-
getSpecificValue
Description copied from class:Facets
Return the count or value for a specific path. Returns -1 if this path doesn't exist, else the count.- Specified by:
getSpecificValue
in classFacets
- Throws:
IOException
-
getAllDims
Description copied from class:Facets
Returns topN labels for any dimension that had hits, sorted by the number of hits that dimension matched; this is used for "sparse" faceting, where many different dimensions were indexed, for example depending on the type of document.- Specified by:
getAllDims
in classFacets
- Throws:
IOException
-