Constructor Detail

• TopKFacetResultsHandler

  public TopKFacetResultsHandler​(TaxonomyReader taxonomyReader,
                                 FacetRequest facetRequest)

  Construct top-K results handler.

  Parameters:

  taxonomyReader - taxonomy reader

  facetRequest - facet request being served

Method Detail

• fetchPartitionResult

  public IntermediateFacetResult fetchPartitionResult​(FacetArrays facetArrays,
                                                      int offset)
                                               throws IOException

  Description copied from class: FacetResultsHandler
  Fetch results of a single partition, given facet arrays for that partition, and based on the matching documents and faceted search parameters.

  Specified by:

  fetchPartitionResult in class FacetResultsHandler

  Parameters:

  facetArrays - facet arrays for the certain partition

  offset - offset in input arrays where partition starts

  Returns:

  temporary facet result, potentially, to be passed back to this result handler for merging, or null in case that constructor parameter, facetRequest, requests an illegal FacetResult, like, e.g., a root node category path that does not exist in constructor parameter taxonomyReader .

  Throws:

  IOException - on error

• mergeResults

  public IntermediateFacetResult mergeResults​(IntermediateFacetResult... tmpResults)
                                       throws IOException

  Description copied from class: FacetResultsHandler
  Merge results of several facet partitions. Logic of the merge is undefined and open for interpretations. For example, a merge implementation could keep top K results. Passed IntermediateFacetResult must be ones that were created by this handler otherwise a ClassCastException is thrown. In addition, all passed IntermediateFacetResult must have the same FacetRequest otherwise an IllegalArgumentException is thrown.

  Specified by:

  mergeResults in class FacetResultsHandler

  Parameters:

  tmpResults - one or more temporary results created by this handler.

  Returns:

  temporary facet result that represents to union, as specified by this handler, of the input temporary facet results.

  Throws:

  IOException - on error.

  See Also:

  IntermediateFacetResult.getFacetRequest()

• renderFacetResult

  public FacetResult renderFacetResult​(IntermediateFacetResult tmpResult)

  Description copied from class: FacetResultsHandler
  Create a facet result from the temporary result.

  Specified by:

  renderFacetResult in class FacetResultsHandler

  Parameters:

  tmpResult - temporary result to be rendered as a FacetResult

• rearrangeFacetResult

  public FacetResult rearrangeFacetResult​(FacetResult facetResult)

  Description copied from class: FacetResultsHandler
  Perform any rearrangement as required on a facet result that has changed after it was rendered.

  Possible use case: a sampling facets accumulator invoked another other facets accumulator on a sample set of documents, obtained rendered facet results, fixed their counts, and now it is needed to sort the results differently according to the fixed counts.

  Specified by:

  rearrangeFacetResult in class FacetResultsHandler

  Parameters:

  facetResult - result to be rearranged.

  See Also:

  FacetResultNode.setValue(double)

• labelResult

  public void labelResult​(FacetResult facetResult)
                   throws IOException

  Description copied from class: FacetResultsHandler
  Label results according to settings in FacetRequest, such as FacetRequest.getNumLabel(). Usually invoked by FacetsAccumulator.accumulate(ScoredDocIDs)

  Specified by:

  labelResult in class FacetResultsHandler

  Parameters:

  facetResult - facet result to be labeled.

  Throws:

  IOException - on error