package org.apache.lucene.search.spans; /** * 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. */ import java.io.IOException; import org.apache.lucene.search.Explanation; import org.apache.lucene.search.Weight; import org.apache.lucene.search.Scorer; import org.apache.lucene.search.Similarity; /** * Public for extension only. */ public class SpanScorer extends Scorer { protected Spans spans; protected Weight weight; protected byte[] norms; protected float value; /** @deprecated not needed anymore */ protected boolean firstTime = true; protected boolean more = true; protected int doc; protected int[] sorts = new int[Scorer.numSort]; protected float freq; protected SpanScorer(Spans spans, Weight weight, Similarity similarity, byte[] norms) throws IOException { super(similarity); this.spans = spans; this.norms = norms; this.weight = weight; this.value = weight.getValue(); if (this.spans.next()) { doc = -1; } else { doc = NO_MORE_DOCS; more = false; } } /** @deprecated use {@link #nextDoc()} instead. */ public boolean next() throws IOException { return nextDoc() != NO_MORE_DOCS; } public int nextDoc() throws IOException { if (!setFreqCurrentDoc()) { doc = NO_MORE_DOCS; } return doc; } /** @deprecated use {@link #advance(int)} instead. */ public boolean skipTo(int target) throws IOException { return advance(target) != NO_MORE_DOCS; } public int advance(int target) throws IOException { if (!more) { return doc = NO_MORE_DOCS; } if (spans.doc() < target) { // setFreqCurrentDoc() leaves spans.doc() ahead more = spans.skipTo(target); } if (!setFreqCurrentDoc()) { doc = NO_MORE_DOCS; } return doc; } protected boolean setFreqCurrentDoc() throws IOException { if (!more) { return false; } doc = spans.doc(); freq = 0.0f; do { int matchLength = spans.end() - spans.start(); freq += getSimilarity().sloppyFreq(matchLength); more = spans.next(); } while (more && (doc == spans.doc())); return true; } /** @deprecated use {@link #docID()} instead. */ public int doc() { return doc; } public int docID() { return doc; } public float score() throws IOException { float raw = getSimilarity().tf(freq) * value; // raw score return norms == null? raw : raw * Similarity.decodeNorm(norms[doc]); // normalize } public Explanation explain(final int doc) throws IOException { Explanation tfExplanation = new Explanation(); int expDoc = advance(doc); float phraseFreq = (expDoc == doc) ? freq : 0.0f; tfExplanation.setValue(getSimilarity().tf(phraseFreq)); tfExplanation.setDescription("tf(phraseFreq=" + phraseFreq + ")"); return tfExplanation; } public int getSort(int fieldNumber) { throw new UnsupportedOperationException(); } public int[] getSorts() { throw new UnsupportedOperationException(); } }