Module org.apache.lucene.facet
Package org.apache.lucene.facet.taxonomy

Class TaxonomyFacetLabels.FacetLabelReader

java.lang.Object
org.apache.lucene.facet.taxonomy.TaxonomyFacetLabels.FacetLabelReader
Enclosing class:
TaxonomyFacetLabels
public class TaxonomyFacetLabels.FacetLabelReader extends Object
Utility class to retrieve facet labels for multiple documents.

  • Field Details

    • ordinalValues

      private final SortedNumericDocValues ordinalValues
      By default, we store taxonomy ordinals in SortedNumericDocValues field

    • currentDocId

      private int currentDocId

    • currentDocHasValues

      private boolean currentDocHasValues

    • currentPos

      private int currentPos

    • currentDocOrdinalCount

      private int currentDocOrdinalCount

    • parents

      private ParallelTaxonomyArrays.IntArray parents

  • Constructor Details

  • Method Details

    • nextFacetLabel

      public FacetLabel nextFacetLabel(int docId) throws IOException
      Retrieves the next FacetLabel for the specified docId, or null if there are no more. This method has state: if the provided docId is the same as the previous invocation, it returns the next FacetLabel for that document. Otherwise, it advances to the new docId and provides the first FacetLabel for that document, or null if that document has no indexed facets. Each new docId must be in strictly monotonic (increasing) order.

      NOTE: The returned FacetLabels may not be in the same order in which they were indexed

      Parameters:
      docId - input docId provided in monotonic (non-decreasing) order
      Returns:
      the first or next FacetLabel, or null if there are no more
      Throws:
      IOException - when a low-level IO issue occurs
      IllegalArgumentException - if docId provided is less than docId supplied in an earlier invocation

    • isDescendant

      private boolean isDescendant(int ord, int ancestorOrd)

    • nextFacetLabel

      public FacetLabel nextFacetLabel(int docId, String facetDimension) throws IOException
      Retrieves the next FacetLabel for the specified docId under the requested facetDimension, or null if there are no more. This method has state: if the provided docId is the same as the previous invocation, it returns the next FacetLabel for that document. Otherwise, it advances to the new docId and provides the first FacetLabel for that document, or null if that document has no indexed facets. Each new docId must be in strictly monotonic (increasing) order.

      NOTE: This method loads the int[] parents array from the taxonomy index. The returned FacetLabels may not be in the same order in which they were indexed.

      Parameters:
      docId - input docId provided in non-decreasing order
      Returns:
      the first or next FacetLabel, or null if there are no more
      Throws:
      IOException - if TaxonomyReader has problems getting path for an ordinal
      IllegalArgumentException - if docId provided is less than docId supplied in an earlier invocation
      IllegalArgumentException - if facetDimension is null