| package org.apache.lucene.search; |
| |
| /* |
| * 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; |
| |
| /** |
| * Re-scores the topN results ({@link TopDocs}) from an original |
| * query. See {@link QueryRescorer} for an actual |
| * implementation. Typically, you run a low-cost |
| * first-pass query across the entire index, collecting the |
| * top few hundred hits perhaps, and then use this class to |
| * mix in a more costly second pass scoring. |
| * |
| * <p>See {@link |
| * QueryRescorer#rescore(IndexSearcher,TopDocs,Query,double,int)} |
| * for a simple static method to call to rescore using a 2nd |
| * pass {@link Query}. |
| * |
| * @lucene.experimental |
| */ |
| |
| public abstract class Rescorer { |
| |
| /** |
| * Rescore an initial first-pass {@link TopDocs}. |
| * |
| * @param searcher {@link IndexSearcher} used to produce the |
| * first pass topDocs |
| * @param firstPassTopDocs Hits from the first pass |
| * search. It's very important that these hits were |
| * produced by the provided searcher; otherwise the doc |
| * IDs will not match! |
| * @param topN How many re-scored hits to return |
| */ |
| public abstract TopDocs rescore(IndexSearcher searcher, TopDocs firstPassTopDocs, int topN) throws IOException; |
| |
| /** |
| * Explains how the score for the specified document was |
| * computed. |
| */ |
| public abstract Explanation explain(IndexSearcher searcher, Explanation firstPassExplanation, int docID) throws IOException; |
| } |