Java tutorial
/* * 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. */ package org.apache.lucene.facet.range; import java.io.IOException; import java.util.List; import org.apache.lucene.document.FloatDocValuesField; import org.apache.lucene.facet.Facets; import org.apache.lucene.facet.FacetsCollector; import org.apache.lucene.facet.FacetsCollector.MatchingDocs; import org.apache.lucene.index.IndexReaderContext; import org.apache.lucene.index.ReaderUtil; import org.apache.lucene.search.DocIdSetIterator; import org.apache.lucene.search.DoubleValues; import org.apache.lucene.search.DoubleValuesSource; import org.apache.lucene.search.IndexSearcher; import org.apache.lucene.search.Query; import org.apache.lucene.search.ScoreMode; import org.apache.lucene.search.Scorer; import org.apache.lucene.search.Weight; import org.apache.lucene.util.NumericUtils; /** {@link Facets} implementation that computes counts for * dynamic double ranges from a provided {@link * DoubleValuesSource}. Use this for dimensions that change in real-time (e.g. a * relative time based dimension like "Past day", "Past 2 * days", etc.) or that change for each request (e.g. * distance from the user's location, "< 1 km", "< 2 km", * etc.). * * If you have indexed your field using {@link * FloatDocValuesField}, then you should use a DoubleValuesSource * generated from {@link DoubleValuesSource#fromFloatField(String)}. * * @lucene.experimental */ public class DoubleRangeFacetCounts extends RangeFacetCounts { /** * Create {@code RangeFacetCounts}, using {@link DoubleValues} from the specified field. * * N.B This assumes that the field was indexed with {@link org.apache.lucene.document.DoubleDocValuesField}. * For float-valued fields, use {@link #DoubleRangeFacetCounts(String, DoubleValuesSource, FacetsCollector, DoubleRange...)} */ public DoubleRangeFacetCounts(String field, FacetsCollector hits, DoubleRange... ranges) throws IOException { this(field, DoubleValuesSource.fromDoubleField(field), hits, ranges); } /** * Create {@code RangeFacetCounts} using the provided {@link DoubleValuesSource} */ public DoubleRangeFacetCounts(String field, DoubleValuesSource valueSource, FacetsCollector hits, DoubleRange... ranges) throws IOException { this(field, valueSource, hits, null, ranges); } /** * Create {@code RangeFacetCounts}, using the provided * {@link DoubleValuesSource}, and using the provided Query as * a fastmatch: only documents matching the query are * checked for the matching ranges. */ public DoubleRangeFacetCounts(String field, DoubleValuesSource valueSource, FacetsCollector hits, Query fastMatchQuery, DoubleRange... ranges) throws IOException { super(field, ranges, fastMatchQuery); count(valueSource, hits.getMatchingDocs()); } private void count(DoubleValuesSource valueSource, List<MatchingDocs> matchingDocs) throws IOException { DoubleRange[] ranges = (DoubleRange[]) this.ranges; LongRange[] longRanges = new LongRange[ranges.length]; for (int i = 0; i < ranges.length; i++) { DoubleRange range = ranges[i]; longRanges[i] = new LongRange(range.label, NumericUtils.doubleToSortableLong(range.min), true, NumericUtils.doubleToSortableLong(range.max), true); } LongRangeCounter counter = new LongRangeCounter(longRanges); int missingCount = 0; for (MatchingDocs hits : matchingDocs) { DoubleValues fv = valueSource.getValues(hits.context, null); totCount += hits.totalHits; final DocIdSetIterator fastMatchDocs; if (fastMatchQuery != null) { final IndexReaderContext topLevelContext = ReaderUtil.getTopLevelContext(hits.context); final IndexSearcher searcher = new IndexSearcher(topLevelContext); searcher.setQueryCache(null); final Weight fastMatchWeight = searcher.createWeight(searcher.rewrite(fastMatchQuery), ScoreMode.COMPLETE_NO_SCORES, 1); Scorer s = fastMatchWeight.scorer(hits.context); if (s == null) { continue; } fastMatchDocs = s.iterator(); } else { fastMatchDocs = null; } DocIdSetIterator docs = hits.bits.iterator(); for (int doc = docs.nextDoc(); doc != DocIdSetIterator.NO_MORE_DOCS;) { if (fastMatchDocs != null) { int fastMatchDoc = fastMatchDocs.docID(); if (fastMatchDoc < doc) { fastMatchDoc = fastMatchDocs.advance(doc); } if (doc != fastMatchDoc) { doc = docs.advance(fastMatchDoc); continue; } } // Skip missing docs: if (fv.advanceExact(doc)) { counter.add(NumericUtils.doubleToSortableLong(fv.doubleValue())); } else { missingCount++; } doc = docs.nextDoc(); } } missingCount += counter.fillCounts(counts); totCount -= missingCount; } }