| /* |
| * 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.document; |
| |
| import java.io.IOException; |
| import java.util.Objects; |
| import java.util.Set; |
| |
| import org.apache.lucene.document.FeatureField.FeatureFunction; |
| import org.apache.lucene.index.ImpactsEnum; |
| import org.apache.lucene.index.IndexReader; |
| import org.apache.lucene.index.LeafReaderContext; |
| import org.apache.lucene.index.PostingsEnum; |
| import org.apache.lucene.index.Term; |
| import org.apache.lucene.index.Terms; |
| import org.apache.lucene.index.TermsEnum; |
| import org.apache.lucene.search.DocIdSetIterator; |
| import org.apache.lucene.search.Explanation; |
| import org.apache.lucene.search.ImpactsDISI; |
| import org.apache.lucene.search.IndexSearcher; |
| import org.apache.lucene.search.Query; |
| import org.apache.lucene.search.QueryVisitor; |
| import org.apache.lucene.search.ScoreMode; |
| import org.apache.lucene.search.Scorer; |
| import org.apache.lucene.search.Weight; |
| import org.apache.lucene.search.similarities.Similarity.SimScorer; |
| import org.apache.lucene.util.BytesRef; |
| |
| final class FeatureQuery extends Query { |
| |
| private final String fieldName; |
| private final String featureName; |
| private final FeatureFunction function; |
| |
| FeatureQuery(String fieldName, String featureName, FeatureFunction function) { |
| this.fieldName = Objects.requireNonNull(fieldName); |
| this.featureName = Objects.requireNonNull(featureName); |
| this.function = Objects.requireNonNull(function); |
| } |
| |
| @Override |
| public Query rewrite(IndexReader reader) throws IOException { |
| FeatureFunction rewritten = function.rewrite(reader); |
| if (function != rewritten) { |
| return new FeatureQuery(fieldName, featureName, rewritten); |
| } |
| return super.rewrite(reader); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == null || getClass() != obj.getClass()) { |
| return false; |
| } |
| FeatureQuery that = (FeatureQuery) obj; |
| return Objects.equals(fieldName, that.fieldName) && |
| Objects.equals(featureName, that.featureName) && |
| Objects.equals(function, that.function); |
| } |
| |
| @Override |
| public int hashCode() { |
| int h = getClass().hashCode(); |
| h = 31 * h + fieldName.hashCode(); |
| h = 31 * h + featureName.hashCode(); |
| h = 31 * h + function.hashCode(); |
| return h; |
| } |
| |
| @Override |
| public Weight createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost) throws IOException { |
| return new Weight(this) { |
| |
| @Override |
| public boolean isCacheable(LeafReaderContext ctx) { |
| return false; |
| } |
| |
| @Override |
| public void extractTerms(Set<Term> terms) { |
| if (scoreMode.needsScores() == false) { |
| // features are irrelevant to highlighting, skip |
| } else { |
| // extracting the term here will help get better scoring with |
| // distributed term statistics if the saturation function is used |
| // and the pivot value is computed automatically |
| terms.add(new Term(fieldName, featureName)); |
| } |
| } |
| |
| @Override |
| public Explanation explain(LeafReaderContext context, int doc) throws IOException { |
| String desc = "weight(" + getQuery() + " in " + doc + ") [" + function + "]"; |
| |
| Terms terms = context.reader().terms(fieldName); |
| if (terms == null) { |
| return Explanation.noMatch(desc + ". Field " + fieldName + " doesn't exist."); |
| } |
| TermsEnum termsEnum = terms.iterator(); |
| if (termsEnum.seekExact(new BytesRef(featureName)) == false) { |
| return Explanation.noMatch(desc + ". Feature " + featureName + " doesn't exist."); |
| } |
| |
| PostingsEnum postings = termsEnum.postings(null, PostingsEnum.FREQS); |
| if (postings.advance(doc) != doc) { |
| return Explanation.noMatch(desc + ". Feature " + featureName + " isn't set."); |
| } |
| |
| return function.explain(fieldName, featureName, boost, postings.freq()); |
| } |
| |
| @Override |
| public Scorer scorer(LeafReaderContext context) throws IOException { |
| Terms terms = context.reader().terms(fieldName); |
| if (terms == null) { |
| return null; |
| } |
| TermsEnum termsEnum = terms.iterator(); |
| if (termsEnum.seekExact(new BytesRef(featureName)) == false) { |
| return null; |
| } |
| |
| final SimScorer scorer = function.scorer(boost); |
| final ImpactsEnum impacts = termsEnum.impacts(PostingsEnum.FREQS); |
| final ImpactsDISI impactsDisi = new ImpactsDISI(impacts, impacts, scorer); |
| |
| return new Scorer(this) { |
| |
| @Override |
| public int docID() { |
| return impacts.docID(); |
| } |
| |
| @Override |
| public float score() throws IOException { |
| return scorer.score(impacts.freq(), 1L); |
| } |
| |
| @Override |
| public DocIdSetIterator iterator() { |
| return impactsDisi; |
| } |
| |
| @Override |
| public int advanceShallow(int target) throws IOException { |
| return impactsDisi.advanceShallow(target); |
| } |
| |
| @Override |
| public float getMaxScore(int upTo) throws IOException { |
| return impactsDisi.getMaxScore(upTo); |
| } |
| |
| @Override |
| public void setMinCompetitiveScore(float minScore) { |
| impactsDisi.setMinCompetitiveScore(minScore); |
| } |
| }; |
| } |
| |
| }; |
| } |
| |
| @Override |
| public void visit(QueryVisitor visitor) { |
| if (visitor.acceptField(fieldName)) { |
| visitor.visitLeaf(this); |
| } |
| } |
| |
| @Override |
| public String toString(String field) { |
| return "FeatureQuery(field=" + fieldName + ", feature=" + featureName + ", function=" + function + ")"; |
| } |
| |
| } |