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* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.index.analysis;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.shingle.ShingleFilter;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.inject.assistedinject.Assisted;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.index.Index;
import org.elasticsearch.index.settings.IndexSettings;
/**
*
*/
public class ShingleTokenFilterFactory extends AbstractTokenFilterFactory {
private final Factory factory;
@Inject
public ShingleTokenFilterFactory(Index index, @IndexSettings Settings indexSettings, @Assisted String name, @Assisted Settings settings) {
super(index, indexSettings, name, settings);
Integer maxShingleSize = settings.getAsInt("max_shingle_size", ShingleFilter.DEFAULT_MAX_SHINGLE_SIZE);
Integer minShingleSize = settings.getAsInt("min_shingle_size", ShingleFilter.DEFAULT_MIN_SHINGLE_SIZE);
Boolean outputUnigrams = settings.getAsBoolean("output_unigrams", true);
Boolean outputUnigramsIfNoShingles = settings.getAsBoolean("output_unigrams_if_no_shingles", false);
String tokenSeparator = settings.get("token_separator", ShingleFilter.DEFAULT_TOKEN_SEPARATOR);
String fillerToken = settings.get("filler_token", ShingleFilter.DEFAULT_FILLER_TOKEN);
factory = new Factory("shingle", minShingleSize, maxShingleSize, outputUnigrams, outputUnigramsIfNoShingles, tokenSeparator, fillerToken);
}
@Override
public TokenStream create(TokenStream tokenStream) {
return factory.create(tokenStream);
}
public Factory getInnerFactory() {
return this.factory;
}
public static final class Factory implements TokenFilterFactory {
private final int maxShingleSize;
private final boolean outputUnigrams;
private final boolean outputUnigramsIfNoShingles;
private final String tokenSeparator;
private final String fillerToken;
private int minShingleSize;
private final String name;
public Factory(String name) {
this(name, ShingleFilter.DEFAULT_MIN_SHINGLE_SIZE, ShingleFilter.DEFAULT_MAX_SHINGLE_SIZE, true, false, ShingleFilter.DEFAULT_TOKEN_SEPARATOR, ShingleFilter.DEFAULT_FILLER_TOKEN);
}
Factory(String name, int minShingleSize, int maxShingleSize, boolean outputUnigrams, boolean outputUnigramsIfNoShingles, String tokenSeparator, String fillerToken) {
this.maxShingleSize = maxShingleSize;
this.outputUnigrams = outputUnigrams;
this.outputUnigramsIfNoShingles = outputUnigramsIfNoShingles;
this.tokenSeparator = tokenSeparator;
this.minShingleSize = minShingleSize;
this.fillerToken = fillerToken;
this.name = name;
}
public TokenStream create(TokenStream tokenStream) {
ShingleFilter filter = new ShingleFilter(tokenStream, minShingleSize, maxShingleSize);
filter.setOutputUnigrams(outputUnigrams);
filter.setOutputUnigramsIfNoShingles(outputUnigramsIfNoShingles);
filter.setTokenSeparator(tokenSeparator);
filter.setFillerToken(fillerToken);
return filter;
}
public int getMaxShingleSize() {
return maxShingleSize;
}
public int getMinShingleSize() {
return minShingleSize;
}
public boolean getOutputUnigrams() {
return outputUnigrams;
}
public boolean getOutputUnigramsIfNoShingles() {
return outputUnigramsIfNoShingles;
}
@Override
public String name() {
return name;
}
}
}