+++ /dev/null
-package org.apache.lucene.facet.search;
-
-import java.io.IOException;
-
-import org.apache.lucene.facet.search.params.FacetRequest;
-import org.apache.lucene.facet.search.results.FacetResult;
-import org.apache.lucene.facet.search.results.FacetResultNode;
-import org.apache.lucene.facet.search.results.IntermediateFacetResult;
-import org.apache.lucene.facet.taxonomy.TaxonomyReader;
-
-/**
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-/**
- * Handler for facet results.
- * <p>
- * The facet results handler provided by the {@link FacetRequest} to
- * a {@link FacetsAccumulator}.
- * <p>
- * First it is used by {@link FacetsAccumulator} to obtain a temporary
- * facet result for each partition and to merge results of several partitions.
- * <p>
- * Later the accumulator invokes the handler to render the results, creating
- * {@link FacetResult} objects.
- * <p>
- * Last the accumulator invokes the handler to label final results.
- *
- * @lucene.experimental
- */
-public abstract class FacetResultsHandler {
-
- /** Taxonomy for which facets are handled */
- protected final TaxonomyReader taxonomyReader;
-
- /**
- * Facet request served by this handler.
- */
- protected final FacetRequest facetRequest;
-
- /**
- * Create a faceted search handler.
- * @param taxonomyReader See {@link #getTaxonomyReader()}.
- * @param facetRequest See {@link #getFacetRequest()}.
- */
- public FacetResultsHandler(TaxonomyReader taxonomyReader,
- FacetRequest facetRequest) {
- this.taxonomyReader = taxonomyReader;
- this.facetRequest = facetRequest;
- }
-
- /**
- * Fetch results of a single partition, given facet arrays for that partition,
- * and based on the matching documents and faceted search parameters.
- *
- * @param arrays
- * facet arrays for the certain partition
- * @param offset
- * offset in input arrays where partition starts
- * @return temporary facet result, potentially, to be passed back to
- * <b>this</b> result handler for merging, or <b>null</b> in case that
- * constructor parameter, <code>facetRequest</code>, requests an
- * illegal FacetResult, like, e.g., a root node category path that
- * does not exist in constructor parameter <code>taxonomyReader</code>
- * .
- * @throws IOException
- * on error
- */
- public abstract IntermediateFacetResult fetchPartitionResult(FacetArrays arrays, int offset) throws IOException;
-
- /**
- * 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 {@link IntermediateFacetResult} must be ones
- * that were created by this handler otherwise a {@link ClassCastException} is
- * thrown. In addition, all passed {@link IntermediateFacetResult} must have
- * the same {@link FacetRequest} otherwise an {@link IllegalArgumentException}
- * is thrown.
- *
- * @param tmpResults one or more temporary results created by <b>this</b>
- * handler.
- * @return temporary facet result that represents to union, as specified by
- * <b>this</b> handler, of the input temporary facet results.
- * @throws IOException on error.
- * @throws ClassCastException if the temporary result passed was not created
- * by this handler
- * @throws IllegalArgumentException if passed <code>facetResults</code> do not
- * have the same {@link FacetRequest}
- * @see IntermediateFacetResult#getFacetRequest()
- */
- public abstract IntermediateFacetResult mergeResults(IntermediateFacetResult... tmpResults)
- throws IOException, ClassCastException, IllegalArgumentException;
-
- /**
- * Create a facet result from the temporary result.
- * @param tmpResult temporary result to be rendered as a {@link FacetResult}
- * @throws IOException on error.
- */
- public abstract FacetResult renderFacetResult(IntermediateFacetResult tmpResult) throws IOException ;
-
- /**
- * Perform any rearrangement as required on a facet result that has changed after
- * it was rendered.
- * <P>
- * 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.
- * @param facetResult result to be rearranged.
- * @see FacetResultNode#setValue(double)
- */
- public abstract FacetResult rearrangeFacetResult(FacetResult facetResult);
-
- /**
- * Label results according to settings in {@link FacetRequest},
- * such as {@link FacetRequest#getNumLabel()}.
- * Usually invoked by {@link FacetsAccumulator#accumulate(ScoredDocIDs)}
- * @param facetResult facet result to be labeled.
- * @throws IOException on error
- */
- public abstract void labelResult (FacetResult facetResult) throws IOException;
-
- /** Return taxonomy reader used for current facets accumulation operation. */
- public final TaxonomyReader getTaxonomyReader() {
- return this.taxonomyReader;
- }
-
- /** Return the facet request served by this handler. */
- public final FacetRequest getFacetRequest() {
- return this.facetRequest;
- }
-
- /**
- * Check if an array contains the partition which contains ordinal
- *
- * @param ordinal
- * checked facet
- * @param facetArrays
- * facet arrays for the certain partition
- * @param offset
- * offset in input arrays where partition starts
- */
- protected boolean isSelfPartition (int ordinal, FacetArrays facetArrays, int offset) {
- int partitionSize = facetArrays.getArraysLength();
- return ordinal / partitionSize == offset / partitionSize;
- }
-
-}
fnp / pylucene.git / blobdiff