/*
* 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 ShingleFilter
. <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>
Since: 3.1 @lucene.spi "shingle"
/**
* 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 /** 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 /** 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;
}
}