| /* |
| * 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.analysis.ngram; |
| |
| import java.util.Map; |
| import org.apache.lucene.analysis.TokenFilter; |
| import org.apache.lucene.analysis.TokenFilterFactory; |
| import org.apache.lucene.analysis.TokenStream; |
| |
| /** |
| * Creates new instances of {@link EdgeNGramTokenFilter}. |
| * |
| * <pre class="prettyprint"> |
| * <fieldType name="text_edgngrm" class="solr.TextField" positionIncrementGap="100"> |
| * <analyzer> |
| * <tokenizer class="solr.WhitespaceTokenizerFactory"/> |
| * <filter class="solr.EdgeNGramFilterFactory" minGramSize="1" maxGramSize="2" preserveOriginal="true"/> |
| * </analyzer> |
| * </fieldType></pre> |
| * |
| * @since 3.1 |
| * @lucene.spi {@value #NAME} |
| */ |
| public class EdgeNGramFilterFactory extends TokenFilterFactory { |
| |
| /** SPI name */ |
| public static final String NAME = "edgeNGram"; |
| |
| private final int maxGramSize; |
| private final int minGramSize; |
| private final boolean preserveOriginal; |
| |
| /** Creates a new EdgeNGramFilterFactory */ |
| public EdgeNGramFilterFactory(Map<String, String> args) { |
| super(args); |
| minGramSize = requireInt(args, "minGramSize"); |
| maxGramSize = requireInt(args, "maxGramSize"); |
| preserveOriginal = |
| getBoolean(args, "preserveOriginal", EdgeNGramTokenFilter.DEFAULT_PRESERVE_ORIGINAL); |
| if (!args.isEmpty()) { |
| throw new IllegalArgumentException("Unknown parameters: " + args); |
| } |
| } |
| |
| /** Default ctor for compatibility with SPI */ |
| public EdgeNGramFilterFactory() { |
| throw defaultCtorException(); |
| } |
| |
| @Override |
| public TokenFilter create(TokenStream input) { |
| return new EdgeNGramTokenFilter(input, minGramSize, maxGramSize, preserveOriginal); |
| } |
| } |