/* * 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.search; import java.io.IOException; import java.util.Objects; import org.apache.lucene.index.LeafReader; import org.apache.lucene.index.NumericDocValues; import org.apache.lucene.search.similarities.Similarity.SimScorer; /** * {@link SimScorer} on a specific {@link LeafReader}. */ public final class LeafSimScorer { private final SimScorer scorer; private final NumericDocValues norms; /** * Sole constructor: Score documents of {@code reader} with {@code scorer}. */ public LeafSimScorer(SimScorer scorer, LeafReader reader, String field, boolean needsScores) throws IOException { this.scorer = Objects.requireNonNull(scorer); norms = needsScores ? reader.getNormValues(field) : null; } /** Return the wrapped {@link SimScorer}. */ public SimScorer getSimScorer() { return scorer; } private long getNormValue(int doc) throws IOException { if (norms != null) { boolean found = norms.advanceExact(doc); assert found; return norms.longValue(); } else { return 1L; // default norm } } /** Score the provided document assuming the given term document frequency. * This method must be called on non-decreasing sequences of doc ids. * @see SimScorer#score(float, long) */ public float score(int doc, float freq) throws IOException { return scorer.score(freq, getNormValue(doc)); } /** Explain the score for the provided document assuming the given term document frequency. * This method must be called on non-decreasing sequences of doc ids. * @see SimScorer#explain(Explanation, long) */ public Explanation explain(int doc, Explanation freqExpl) throws IOException { return scorer.explain(freqExpl, getNormValue(doc)); } }