opennlp.tools.util.featuregen.BrownTokenClassFeatureGenerator Maven / Gradle / Ivy
/*
* 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 opennlp.tools.util.featuregen;
import java.util.List;
/**
* Generates {@link BrownCluster} features for current token and token class.
*/
public class BrownTokenClassFeatureGenerator implements AdaptiveFeatureGenerator {
private final BrownCluster brownLexicon;
/**
* Instantiates a {@link BrownTokenClassFeatureGenerator} via a specified
* {@link BrownCluster}.
*
* @param dict The token {@link BrownCluster dictionary} to use.
*/
public BrownTokenClassFeatureGenerator(BrownCluster dict) {
this.brownLexicon = dict;
}
@Override
public void createFeatures(List features, String[] tokens, int index,
String[] previousOutcomes) {
String wordShape = FeatureGeneratorUtil.tokenFeature(tokens[index]);
List wordClasses = BrownTokenClasses.getWordClasses(tokens[index], brownLexicon);
for (String wordClass : wordClasses) {
features.add("c," + "browncluster" + "=" + wordShape + "," + wordClass);
}
}
}