| /* |
| * 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 org.apache.lucene.search.DocIdSetIterator; |
| import org.apache.lucene.search.Scorer; |
| import org.apache.lucene.search.TwoPhaseIterator; |
| import org.apache.lucene.search.Weight; |
| import org.apache.lucene.search.similarities.Similarity; |
| |
| class IntervalScorer extends Scorer { |
| |
| private final IntervalIterator intervals; |
| private final Similarity.SimScorer simScorer; |
| private final float boost; |
| private final int minExtent; |
| |
| private float freq; |
| private int lastScoredDoc = -1; |
| |
| IntervalScorer(Weight weight, IntervalIterator intervals, int minExtent, float boost, IntervalScoreFunction scoreFunction) { |
| super(weight); |
| this.intervals = intervals; |
| this.minExtent = minExtent; |
| this.boost = boost; |
| this.simScorer = scoreFunction.scorer(boost); |
| } |
| |
| @Override |
| public int docID() { |
| return intervals.docID(); |
| } |
| |
| @Override |
| public float score() throws IOException { |
| ensureFreq(); |
| return simScorer.score(freq, 1); |
| } |
| |
| float freq() throws IOException { |
| ensureFreq(); |
| return freq; |
| } |
| |
| private void ensureFreq() throws IOException { |
| if (lastScoredDoc != docID()) { |
| lastScoredDoc = docID(); |
| freq = 0; |
| do { |
| int length = (intervals.end() - intervals.start() + 1); |
| freq += 1.0 / Math.max(length - minExtent + 1, 1); |
| } |
| while (intervals.nextInterval() != IntervalIterator.NO_MORE_INTERVALS); |
| } |
| } |
| |
| @Override |
| public DocIdSetIterator iterator() { |
| return TwoPhaseIterator.asDocIdSetIterator(twoPhaseIterator()); |
| } |
| |
| @Override |
| public TwoPhaseIterator twoPhaseIterator() { |
| return new TwoPhaseIterator(intervals) { |
| @Override |
| public boolean matches() throws IOException { |
| return intervals.nextInterval() != IntervalIterator.NO_MORE_INTERVALS; |
| } |
| |
| @Override |
| public float matchCost() { |
| return intervals.matchCost(); |
| } |
| }; |
| } |
| |
| @Override |
| public float getMaxScore(int upTo) { |
| return boost; |
| } |
| |
| } |