/* * 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.queries.intervals; import java.io.IOException; import java.util.ArrayList; import java.util.Collection; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import java.util.Objects; import java.util.stream.Collectors; import org.apache.lucene.util.PriorityQueue; class UnorderedIntervalsSource extends ConjunctionIntervalsSource { static IntervalsSource build(List<IntervalsSource> sources) { if (sources.size() == 1) { return sources.get(0); } List<IntervalsSource> rewritten = deduplicate(flatten(sources)); if (rewritten.size() == 1) { return rewritten.get(0); } return new UnorderedIntervalsSource(rewritten); } private static List<IntervalsSource> deduplicate(List<IntervalsSource> sources) { Map<IntervalsSource, Integer> counts = new LinkedHashMap<>(); // preserve order for testing for (IntervalsSource source : sources) { counts.compute(source, (k, v) -> v == null ? 1 : v + 1); } List<IntervalsSource> deduplicated = new ArrayList<>(); for (IntervalsSource source : counts.keySet()) { deduplicated.add(RepeatingIntervalsSource.build(source, counts.get(source))); } if (deduplicated.size() == 1 && deduplicated.get(0) instanceof RepeatingIntervalsSource) { ((RepeatingIntervalsSource)deduplicated.get(0)).setName("UNORDERED"); } return deduplicated; } private static List<IntervalsSource> flatten(List<IntervalsSource> sources) { List<IntervalsSource> flattened = new ArrayList<>(); for (IntervalsSource s : sources) { if (s instanceof UnorderedIntervalsSource) { flattened.addAll(((UnorderedIntervalsSource)s).subSources); } else { flattened.add(s); } } return flattened; } private UnorderedIntervalsSource(List<IntervalsSource> sources) { super(sources, true); } @Override protected IntervalIterator combine(List<IntervalIterator> iterators) { return new UnorderedIntervalIterator(iterators); } @Override public int minExtent() { int minExtent = 0; for (IntervalsSource subSource : subSources) { minExtent += subSource.minExtent(); } return minExtent; } @Override public Collection<IntervalsSource> pullUpDisjunctions() { return Disjunctions.pullUp(subSources, UnorderedIntervalsSource::new); } @Override public int hashCode() { return Objects.hash(this.subSources); } @Override public boolean equals(Object other) { if (other instanceof UnorderedIntervalsSource == false) return false; UnorderedIntervalsSource o = (UnorderedIntervalsSource) other; return Objects.equals(this.subSources, o.subSources); } @Override public String toString() { return "UNORDERED(" + subSources.stream().map(IntervalsSource::toString).collect(Collectors.joining(",")) + ")"; } private static class UnorderedIntervalIterator extends ConjunctionIntervalIterator { private final PriorityQueue<IntervalIterator> queue; private final IntervalIterator[] subIterators; int start = -1, end = -1, slop, queueEnd; UnorderedIntervalIterator(List<IntervalIterator> subIterators) { super(subIterators); this.queue = new PriorityQueue<IntervalIterator>(subIterators.size()) { @Override protected boolean lessThan(IntervalIterator a, IntervalIterator b) { return a.start() < b.start() || (a.start() == b.start() && a.end() >= b.end()); } }; this.subIterators = new IntervalIterator[subIterators.size()]; for (int i = 0; i < subIterators.size(); i++) { this.subIterators[i] = subIterators.get(i); } } @Override public int start() { return start; } @Override public int end() { return end; } void updateRightExtreme(IntervalIterator it) { int itEnd = it.end(); if (itEnd > queueEnd) { queueEnd = itEnd; } } @Override public int nextInterval() throws IOException { // first, find a matching interval while (this.queue.size() == subIterators.length && queue.top().start() == start) { IntervalIterator it = queue.pop(); if (it != null && it.nextInterval() != IntervalIterator.NO_MORE_INTERVALS) { queue.add(it); updateRightExtreme(it); } } if (this.queue.size() < subIterators.length) return start = end = IntervalIterator.NO_MORE_INTERVALS; // then, minimize it do { start = queue.top().start(); end = queueEnd; slop = width(); for (IntervalIterator it : subIterators) { slop -= it.width(); } if (queue.top().end() == end) return start; IntervalIterator it = queue.pop(); if (it != null && it.nextInterval() != IntervalIterator.NO_MORE_INTERVALS) { queue.add(it); updateRightExtreme(it); } } while (this.queue.size() == subIterators.length && end == queueEnd); return start; } @Override public int gaps() { return slop; } @Override protected void reset() throws IOException { queueEnd = start = end = -1; this.queue.clear(); for (IntervalIterator it : subIterators) { if (it.nextInterval() == NO_MORE_INTERVALS) { break; } queue.add(it); updateRightExtreme(it); } } } }