opennlp.tools.util.featuregen.TokenFeatureGenerator 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;
import opennlp.tools.util.StringUtil;
/**
* Generates a feature which contains the token itself.
*/
public class TokenFeatureGenerator implements AdaptiveFeatureGenerator {
private static final String WORD_PREFIX = "w";
private boolean lowercase;
public TokenFeatureGenerator(boolean lowercase) {
this.lowercase = lowercase;
}
public TokenFeatureGenerator() {
this(true);
}
public void createFeatures(List features, String[] tokens, int index, String[] preds) {
if (lowercase) {
features.add(WORD_PREFIX + "=" + StringUtil.toLowerCase(tokens[index]));
}
else {
features.add(WORD_PREFIX + "=" + tokens[index]);
}
}
}