org.apache.lucene.facet.sampling
Class SamplingWrapper
java.lang.Object
org.apache.lucene.facet.search.FacetsAccumulator
org.apache.lucene.facet.search.TaxonomyFacetsAccumulator
org.apache.lucene.facet.old.OldFacetsAccumulator
org.apache.lucene.facet.sampling.SamplingWrapper
public class SamplingWrapper
- extends OldFacetsAccumulator
Wrap any Facets Accumulator with sampling.
Note: Sampling accumulation (Accumulation over a sampled-set of the results),
does not guarantee accurate values for
FacetResult.getNumValidDescendants()
.
- WARNING: This API is experimental and might change in incompatible ways in the next release.
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
SamplingWrapper
public SamplingWrapper(OldFacetsAccumulator delegee,
Sampler sampler)
accumulate
public List<FacetResult> accumulate(ScoredDocIDs docids)
throws IOException
- Overrides:
accumulate
in class OldFacetsAccumulator
- Throws:
IOException
getComplementThreshold
public double getComplementThreshold()
- Description copied from class:
OldFacetsAccumulator
- Returns the complement threshold.
- Overrides:
getComplementThreshold
in class OldFacetsAccumulator
- See Also:
OldFacetsAccumulator.setComplementThreshold(double)
setComplementThreshold
public void setComplementThreshold(double complementThreshold)
- Description copied from class:
OldFacetsAccumulator
- Set the complement threshold.
This threshold will dictate whether the complements optimization is applied.
The optimization is to count for less documents. It is useful when the same
FacetSearchParams are used for varying sets of documents. The first time
complements is used the "total counts" are computed - counting for all the
documents in the collection. Then, only the complementing set of documents
is considered, and used to decrement from the overall counts, thereby
walking through less documents, which is faster.
For the default settings see OldFacetsAccumulator.DEFAULT_COMPLEMENT_THRESHOLD
.
To forcing complements in all cases pass OldFacetsAccumulator.FORCE_COMPLEMENT
.
This is mostly useful for testing purposes, as forcing complements when only
tiny fraction of available documents match the query does not make sense and
would incur performance degradations.
To disable complements pass OldFacetsAccumulator.DISABLE_COMPLEMENT
.
- Overrides:
setComplementThreshold
in class OldFacetsAccumulator
- Parameters:
complementThreshold
- the complement threshold to set- See Also:
OldFacetsAccumulator.getComplementThreshold()
Copyright © 2000-2013 Apache Software Foundation. All Rights Reserved.