+++ /dev/null
-package org.apache.lucene.search.function;
-
-/**
- * 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.index.IndexReader;
-import org.apache.lucene.search.Explanation;
-import org.apache.lucene.search.FieldCache; // for javadocs
-
-/**
- * An instance of this subclass should be returned by
- * {@link CustomScoreQuery#getCustomScoreProvider}, if you want
- * to modify the custom score calculation of a {@link CustomScoreQuery}.
- * <p>Since Lucene 2.9, queries operate on each segment of an index separately,
- * so the protected {@link #reader} field can be used to resolve doc IDs,
- * as the supplied <code>doc</code> ID is per-segment and without knowledge
- * of the IndexReader you cannot access the document or {@link FieldCache}.
- *
- * @lucene.experimental
- * @since 2.9.2
- */
-public class CustomScoreProvider {
-
- protected final IndexReader reader;
-
- /**
- * Creates a new instance of the provider class for the given {@link IndexReader}.
- */
- public CustomScoreProvider(IndexReader reader) {
- this.reader = reader;
- }
-
- /**
- * Compute a custom score by the subQuery score and a number of
- * {@link ValueSourceQuery} scores.
- * <p>
- * Subclasses can override this method to modify the custom score.
- * <p>
- * If your custom scoring is different than the default herein you
- * should override at least one of the two customScore() methods.
- * If the number of ValueSourceQueries is always < 2 it is
- * sufficient to override the other
- * {@link #customScore(int, float, float) customScore()}
- * method, which is simpler.
- * <p>
- * The default computation herein is a multiplication of given scores:
- * <pre>
- * ModifiedScore = valSrcScore * valSrcScores[0] * valSrcScores[1] * ...
- * </pre>
- *
- * @param doc id of scored doc.
- * @param subQueryScore score of that doc by the subQuery.
- * @param valSrcScores scores of that doc by the ValueSourceQuery.
- * @return custom score.
- */
- public float customScore(int doc, float subQueryScore, float valSrcScores[]) throws IOException {
- if (valSrcScores.length == 1) {
- return customScore(doc, subQueryScore, valSrcScores[0]);
- }
- if (valSrcScores.length == 0) {
- return customScore(doc, subQueryScore, 1);
- }
- float score = subQueryScore;
- for(int i = 0; i < valSrcScores.length; i++) {
- score *= valSrcScores[i];
- }
- return score;
- }
-
- /**
- * Compute a custom score by the subQuery score and the ValueSourceQuery score.
- * <p>
- * Subclasses can override this method to modify the custom score.
- * <p>
- * If your custom scoring is different than the default herein you
- * should override at least one of the two customScore() methods.
- * If the number of ValueSourceQueries is always < 2 it is
- * sufficient to override this customScore() method, which is simpler.
- * <p>
- * The default computation herein is a multiplication of the two scores:
- * <pre>
- * ModifiedScore = subQueryScore * valSrcScore
- * </pre>
- *
- * @param doc id of scored doc.
- * @param subQueryScore score of that doc by the subQuery.
- * @param valSrcScore score of that doc by the ValueSourceQuery.
- * @return custom score.
- */
- public float customScore(int doc, float subQueryScore, float valSrcScore) throws IOException {
- return subQueryScore * valSrcScore;
- }
-
- /**
- * Explain the custom score.
- * Whenever overriding {@link #customScore(int, float, float[])},
- * this method should also be overridden to provide the correct explanation
- * for the part of the custom scoring.
- *
- * @param doc doc being explained.
- * @param subQueryExpl explanation for the sub-query part.
- * @param valSrcExpls explanation for the value source part.
- * @return an explanation for the custom score
- */
- public Explanation customExplain(int doc, Explanation subQueryExpl, Explanation valSrcExpls[]) throws IOException {
- if (valSrcExpls.length == 1) {
- return customExplain(doc, subQueryExpl, valSrcExpls[0]);
- }
- if (valSrcExpls.length == 0) {
- return subQueryExpl;
- }
- float valSrcScore = 1;
- for (int i = 0; i < valSrcExpls.length; i++) {
- valSrcScore *= valSrcExpls[i].getValue();
- }
- Explanation exp = new Explanation( valSrcScore * subQueryExpl.getValue(), "custom score: product of:");
- exp.addDetail(subQueryExpl);
- for (int i = 0; i < valSrcExpls.length; i++) {
- exp.addDetail(valSrcExpls[i]);
- }
- return exp;
- }
-
- /**
- * Explain the custom score.
- * Whenever overriding {@link #customScore(int, float, float)},
- * this method should also be overridden to provide the correct explanation
- * for the part of the custom scoring.
- *
- * @param doc doc being explained.
- * @param subQueryExpl explanation for the sub-query part.
- * @param valSrcExpl explanation for the value source part.
- * @return an explanation for the custom score
- */
- public Explanation customExplain(int doc, Explanation subQueryExpl, Explanation valSrcExpl) throws IOException {
- float valSrcScore = 1;
- if (valSrcExpl != null) {
- valSrcScore *= valSrcExpl.getValue();
- }
- Explanation exp = new Explanation( valSrcScore * subQueryExpl.getValue(), "custom score: product of:");
- exp.addDetail(subQueryExpl);
- exp.addDetail(valSrcExpl);
- return exp;
- }
-
-}
fnp / pylucene.git / blobdiff