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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.core.TypeTokenFilter;
import org.elasticsearch.ElasticsearchIllegalArgumentException;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.inject.assistedinject.Assisted;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.env.Environment;
import org.elasticsearch.index.Index;
import org.elasticsearch.index.settings.IndexSettings;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
/**
* A {@link TokenFilterFactory} for {@link TypeFilter}. This filter only
* keep tokens that are contained in the set configured via
* {@value #KEEP_TYPES_KEY} setting.
* <p/>
* Configuration options:
* <p/>
* <ul>
* <li>{@value #KEEP_TYPES_KEY} the array of words / tokens to keep.</li>
* </ul>
*/
@AnalysisSettingsRequired
public class KeepTypesFilterFactory extends AbstractTokenFilterFactory {
private final Set<String> keepTypes;
private static final String KEEP_TYPES_KEY = "types";
@Inject
public KeepTypesFilterFactory(Index index, @IndexSettings Settings indexSettings,
Environment env, @Assisted String name, @Assisted Settings settings) {
super(index, indexSettings, name, settings);
final String[] arrayKeepTypes = settings.getAsArray(KEEP_TYPES_KEY, null);
if ((arrayKeepTypes == null)) {
throw new ElasticsearchIllegalArgumentException("keep_types requires `" + KEEP_TYPES_KEY + "` to be configured");
}
this.keepTypes = new HashSet<>(Arrays.asList(arrayKeepTypes));
}
@Override
public TokenStream create(TokenStream tokenStream) {
return new TypeTokenFilter(tokenStream, keepTypes, true);
}
}