org.apache.lucene.facet.search
Class DepthOneFacetResultsHandler

java.lang.Object
  org.apache.lucene.facet.search.FacetResultsHandler
      org.apache.lucene.facet.search.DepthOneFacetResultsHandler

Direct Known Subclasses:

FloatFacetResultsHandler, IntFacetResultsHandler

public abstract class DepthOneFacetResultsHandler
extends FacetResultsHandler

A FacetResultsHandler which counts the top-K facets at depth 1 only and always labels all result categories. The results are always sorted by value, in descending order. Sub-classes are responsible to pull the values from the corresponding FacetArrays.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

Fields inherited from class org.apache.lucene.facet.search.FacetResultsHandler

facetArrays, facetRequest, taxonomyReader

Constructor Summary

DepthOneFacetResultsHandler(TaxonomyReader taxonomyReader, FacetRequest facetRequest, FacetArrays facetArrays)

Method Summary

protected abstract void	addSiblings(int ordinal, int[] siblings, ArrayList<FacetResultNode> nodes) Add the siblings of ordinal to the given list.
protected abstract int	addSiblings(int ordinal, int[] siblings, PriorityQueue<FacetResultNode> pq) Add the siblings of ordinal to the given PriorityQueue.
FacetResult	compute() Computes the FacetResult for the given FacetArrays.
protected abstract double	valueOf(int ordinal) Returnt the value of the requested ordinal.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DepthOneFacetResultsHandler

public DepthOneFacetResultsHandler(TaxonomyReader taxonomyReader,
                                   FacetRequest facetRequest,
                                   FacetArrays facetArrays)

Method Detail

valueOf

protected abstract double valueOf(int ordinal)

Returnt the value of the requested ordinal. Called once for the result root.

addSiblings

protected abstract void addSiblings(int ordinal,
                                    int[] siblings,
                                    ArrayList<FacetResultNode> nodes)
                             throws IOException

Add the siblings of ordinal to the given list. This is called whenever the number of results is too high (> taxonomy size), instead of adding them to a PriorityQueue.

Throws:

IOException

addSiblings

protected abstract int addSiblings(int ordinal,
                                   int[] siblings,
                                   PriorityQueue<FacetResultNode> pq)

Add the siblings of ordinal to the given PriorityQueue. The given PriorityQueue is already filled with sentinel objects, so implementations are encouraged to use PriorityQueue.top() and PriorityQueue.updateTop() for best performance.

compute

public final FacetResult compute()
                          throws IOException

Description copied from class: FacetResultsHandler

Computes the FacetResult for the given FacetArrays.

Specified by:

compute in class FacetResultsHandler

Throws:

IOException