| /* |
| * 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.highlight; |
| |
| import java.io.IOException; |
| |
| import org.apache.lucene.analysis.TokenStream; |
| |
| /** |
| * A Scorer is responsible for scoring a stream of tokens. These token scores |
| * can then be used to compute {@link TextFragment} scores. |
| */ |
| public interface Scorer { |
| |
| /** |
| * Called to init the Scorer with a {@link TokenStream}. You can grab references to |
| * the attributes you are interested in here and access them from {@link #getTokenScore()}. |
| * |
| * @param tokenStream the {@link TokenStream} that will be scored. |
| * @return either a {@link TokenStream} that the Highlighter should continue using (eg |
| * if you read the tokenSream in this method) or null to continue |
| * using the same {@link TokenStream} that was passed in. |
| * @throws IOException If there is a low-level I/O error |
| */ |
| public TokenStream init(TokenStream tokenStream) throws IOException; |
| |
| /** |
| * Called when a new fragment is started for consideration. |
| * |
| * @param newFragment the fragment that will be scored next |
| */ |
| public void startFragment(TextFragment newFragment); |
| |
| /** |
| * Called for each token in the current fragment. The {@link Highlighter} will |
| * increment the {@link TokenStream} passed to init on every call. |
| * |
| * @return a score which is passed to the {@link Highlighter} class to influence the |
| * mark-up of the text (this return value is NOT used to score the |
| * fragment) |
| */ |
| public float getTokenScore(); |
| |
| /** |
| * Called when the {@link Highlighter} has no more tokens for the current fragment - |
| * the Scorer returns the weighting it has derived for the most recent |
| * fragment, typically based on the results of {@link #getTokenScore()}. |
| * |
| */ |
| public float getFragmentScore(); |
| |
| } |