| /* |
| * 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.shingle; |
| |
| |
| import org.apache.lucene.analysis.TokenStream; |
| import org.apache.lucene.analysis.util.TokenFilterFactory; |
| |
| import java.util.Map; |
| |
| /** |
| * Factory for {@link ShingleFilter}. |
| * <pre class="prettyprint"> |
| * <fieldType name="text_shingle" class="solr.TextField" positionIncrementGap="100"> |
| * <analyzer> |
| * <tokenizer class="solr.WhitespaceTokenizerFactory"/> |
| * <filter class="solr.ShingleFilterFactory" minShingleSize="2" maxShingleSize="2" |
| * outputUnigrams="true" outputUnigramsIfNoShingles="false" tokenSeparator=" " fillerToken="_"/> |
| * </analyzer> |
| * </fieldType></pre> |
| * |
| * @since 3.1 |
| * @lucene.spi {@value #NAME} |
| */ |
| public class ShingleFilterFactory extends TokenFilterFactory { |
| |
| /** SPI name */ |
| public static final String NAME = "shingle"; |
| |
| private final int minShingleSize; |
| private final int maxShingleSize; |
| private final boolean outputUnigrams; |
| private final boolean outputUnigramsIfNoShingles; |
| private final String tokenSeparator; |
| private final String fillerToken; |
| |
| /** Creates a new ShingleFilterFactory */ |
| public ShingleFilterFactory(Map<String, String> args) { |
| super(args); |
| maxShingleSize = getInt(args, "maxShingleSize", ShingleFilter.DEFAULT_MAX_SHINGLE_SIZE); |
| if (maxShingleSize < 2) { |
| throw new IllegalArgumentException("Invalid maxShingleSize (" + maxShingleSize + ") - must be at least 2"); |
| } |
| minShingleSize = getInt(args, "minShingleSize", ShingleFilter.DEFAULT_MIN_SHINGLE_SIZE); |
| if (minShingleSize < 2) { |
| throw new IllegalArgumentException("Invalid minShingleSize (" + minShingleSize + ") - must be at least 2"); |
| } |
| if (minShingleSize > maxShingleSize) { |
| throw new IllegalArgumentException |
| ("Invalid minShingleSize (" + minShingleSize + ") - must be no greater than maxShingleSize (" + maxShingleSize + ")"); |
| } |
| outputUnigrams = getBoolean(args, "outputUnigrams", true); |
| outputUnigramsIfNoShingles = getBoolean(args, "outputUnigramsIfNoShingles", false); |
| tokenSeparator = get(args, "tokenSeparator", ShingleFilter.DEFAULT_TOKEN_SEPARATOR); |
| fillerToken = get(args, "fillerToken", ShingleFilter.DEFAULT_FILLER_TOKEN); |
| if (!args.isEmpty()) { |
| throw new IllegalArgumentException("Unknown parameters: " + args); |
| } |
| } |
| |
| @Override |
| public ShingleFilter create(TokenStream input) { |
| ShingleFilter r = new ShingleFilter(input, minShingleSize, maxShingleSize); |
| r.setOutputUnigrams(outputUnigrams); |
| r.setOutputUnigramsIfNoShingles(outputUnigramsIfNoShingles); |
| r.setTokenSeparator(tokenSeparator); |
| r.setFillerToken(fillerToken); |
| return r; |
| } |
| } |
| |