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* the Apache License, Version 2.0 (the "License"); you may
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* 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
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package org.elasticsearch.analysis.common;
import org.apache.lucene.analysis.CharArraySet;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter;
import org.apache.lucene.analysis.miscellaneous.WordDelimiterIterator;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.env.Environment;
import org.elasticsearch.index.IndexSettings;
import org.elasticsearch.index.analysis.AbstractTokenFilterFactory;
import org.elasticsearch.index.analysis.Analysis;
import java.util.List;
import java.util.Set;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.CATENATE_ALL;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.CATENATE_NUMBERS;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.CATENATE_WORDS;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.GENERATE_NUMBER_PARTS;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.GENERATE_WORD_PARTS;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.PRESERVE_ORIGINAL;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.SPLIT_ON_CASE_CHANGE;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.SPLIT_ON_NUMERICS;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.STEM_ENGLISH_POSSESSIVE;
import static org.elasticsearch.analysis.common.WordDelimiterTokenFilterFactory.parseTypes;
public class WordDelimiterGraphTokenFilterFactory extends AbstractTokenFilterFactory {
private final byte[] charTypeTable;
private final int flags;
private final CharArraySet protoWords;
public WordDelimiterGraphTokenFilterFactory(IndexSettings indexSettings, Environment env,
String name, Settings settings) {
super(indexSettings, name, settings);
// Sample Format for the type table:
// $ => DIGIT
// % => DIGIT
// . => DIGIT
// \u002C => DIGIT
// \u200D => ALPHANUM
List<String> charTypeTableValues = Analysis.getWordList(env, settings, "type_table");
if (charTypeTableValues == null) {
this.charTypeTable = WordDelimiterIterator.DEFAULT_WORD_DELIM_TABLE;
} else {
this.charTypeTable = parseTypes(charTypeTableValues);
}
int flags = 0;
// If set, causes parts of words to be generated: "PowerShot" => "Power" "Shot"
flags |= getFlag(GENERATE_WORD_PARTS, settings, "generate_word_parts", true);
// If set, causes number subwords to be generated: "500-42" => "500" "42"
flags |= getFlag(GENERATE_NUMBER_PARTS, settings, "generate_number_parts", true);
// 1, causes maximum runs of word parts to be catenated: "wi-fi" => "wifi"
flags |= getFlag(CATENATE_WORDS, settings, "catenate_words", false);
// If set, causes maximum runs of number parts to be catenated: "500-42" => "50042"
flags |= getFlag(CATENATE_NUMBERS, settings, "catenate_numbers", false);
// If set, causes all subword parts to be catenated: "wi-fi-4000" => "wifi4000"
flags |= getFlag(CATENATE_ALL, settings, "catenate_all", false);
// 1, causes "PowerShot" to be two tokens; ("Power-Shot" remains two parts regards)
flags |= getFlag(SPLIT_ON_CASE_CHANGE, settings, "split_on_case_change", true);
// If set, includes original words in subwords: "500-42" => "500" "42" "500-42"
flags |= getFlag(PRESERVE_ORIGINAL, settings, "preserve_original", false);
// 1, causes "j2se" to be three tokens; "j" "2" "se"
flags |= getFlag(SPLIT_ON_NUMERICS, settings, "split_on_numerics", true);
// If set, causes trailing "'s" to be removed for each subword: "O'Neil's" => "O", "Neil"
flags |= getFlag(STEM_ENGLISH_POSSESSIVE, settings, "stem_english_possessive", true);
// If not null is the set of tokens to protect from being delimited
Set<?> protectedWords = Analysis.getWordSet(env, indexSettings.getIndexVersionCreated(),
settings, "protected_words");
this.protoWords = protectedWords == null ? null : CharArraySet.copy(protectedWords);
this.flags = flags;
}
@Override
public TokenStream create(TokenStream tokenStream) {
return new WordDelimiterGraphFilter(tokenStream, charTypeTable, flags, protoWords);
}
private int getFlag(int flag, Settings settings, String key, boolean defaultValue) {
if (settings.getAsBoolean(key, defaultValue)) {
return flag;
}
return 0;
}
}