/*
* 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.Tokenizer;
import org.apache.lucene.analysis.ja.JapaneseTokenizer;
import org.apache.lucene.analysis.ja.JapaneseTokenizer.Mode;
import org.apache.lucene.analysis.ja.dict.UserDictionary;
import org.elasticsearch.ElasticsearchException;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.env.Environment;
import org.elasticsearch.index.IndexSettings;
import java.io.IOException;
import java.io.Reader;
public class KuromojiTokenizerFactory extends AbstractTokenizerFactory {
private static final String USER_DICT_OPTION = "user_dictionary";
private static final String NBEST_COST = "nbest_cost";
private static final String NBEST_EXAMPLES = "nbest_examples";
private final UserDictionary userDictionary;
private final Mode mode;
private final String nBestExamples;
private final int nBestCost;
private boolean discartPunctuation;
public KuromojiTokenizerFactory(IndexSettings indexSettings, Environment env, String name, Settings settings) {
super(indexSettings, name, settings);
mode = getMode(settings);
userDictionary = getUserDictionary(env, settings);
discartPunctuation = settings
.getAsBooleanLenientForPreEs6Indices(indexSettings.getIndexVersionCreated(), "discard_punctuation", true, deprecationLogger);
nBestCost = settings.getAsInt(NBEST_COST, -1);
nBestExamples = settings.get(NBEST_EXAMPLES);
}
public static UserDictionary getUserDictionary(Environment env, Settings settings) {
try {
final Reader reader = Analysis.getReaderFromFile(env, settings, USER_DICT_OPTION);
if (reader == null) {
return null;
} else {
try {
return UserDictionary.open(reader);
} finally {
reader.close();
}
}
} catch (IOException e) {
throw new ElasticsearchException("failed to load kuromoji user dictionary", e);
}
}
public static JapaneseTokenizer.Mode getMode(Settings settings) {
JapaneseTokenizer.Mode mode = JapaneseTokenizer.DEFAULT_MODE;
String modeSetting = settings.get("mode", null);
if (modeSetting != null) {
if ("search".equalsIgnoreCase(modeSetting)) {
mode = JapaneseTokenizer.Mode.SEARCH;
} else if ("normal".equalsIgnoreCase(modeSetting)) {
mode = JapaneseTokenizer.Mode.NORMAL;
} else if ("extended".equalsIgnoreCase(modeSetting)) {
mode = JapaneseTokenizer.Mode.EXTENDED;
}
}
return mode;
}
@Override
public Tokenizer create() {
JapaneseTokenizer t = new JapaneseTokenizer(userDictionary, discartPunctuation, mode);
int nBestCost = this.nBestCost;
if (nBestExamples != null) {
nBestCost = Math.max(nBestCost, t.calcNBestCost(nBestExamples));
}
t.setNBestCost(nBestCost);
return t;
}
}