opennlp.tools.stemmer.snowball.SnowballStemmer 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.stemmer.snowball;
import opennlp.tools.stemmer.Stemmer;
public class SnowballStemmer implements Stemmer {
public enum ALGORITHM {
DANISH,
DUTCH,
ENGLISH,
FINNISH,
FRENCH,
GERMAN,
HUNGARIAN,
ITALIAN,
NORWEGIAN,
PORTER,
PORTUGUESE,
ROMANIAN,
RUSSIAN,
SPANISH,
SWEDISH,
TURKISH
}
private final AbstractSnowballStemmer stemmer;
private final int repeat;
public SnowballStemmer(ALGORITHM algorithm, int repeat) {
this.repeat = repeat;
if (ALGORITHM.DANISH.equals(algorithm)) {
stemmer = new danishStemmer();
}
else if (ALGORITHM.DUTCH.equals(algorithm)) {
stemmer = new dutchStemmer();
}
else if (ALGORITHM.ENGLISH.equals(algorithm)) {
stemmer = new englishStemmer();
}
else if (ALGORITHM.FINNISH.equals(algorithm)) {
stemmer = new finnishStemmer();
}
else if (ALGORITHM.FRENCH.equals(algorithm)) {
stemmer = new frenchStemmer();
}
else if (ALGORITHM.GERMAN.equals(algorithm)) {
stemmer = new germanStemmer();
}
else if (ALGORITHM.HUNGARIAN.equals(algorithm)) {
stemmer = new hungarianStemmer();
}
else if (ALGORITHM.ITALIAN.equals(algorithm)) {
stemmer = new italianStemmer();
}
else if (ALGORITHM.NORWEGIAN.equals(algorithm)) {
stemmer = new norwegianStemmer();
}
else if (ALGORITHM.PORTER.equals(algorithm)) {
stemmer = new porterStemmer();
}
else if (ALGORITHM.PORTUGUESE.equals(algorithm)) {
stemmer = new portugueseStemmer();
}
else if (ALGORITHM.ROMANIAN.equals(algorithm)) {
stemmer = new romanianStemmer();
}
else if (ALGORITHM.RUSSIAN.equals(algorithm)) {
stemmer = new russianStemmer();
}
else if (ALGORITHM.SPANISH.equals(algorithm)) {
stemmer = new spanishStemmer();
}
else if (ALGORITHM.SWEDISH.equals(algorithm)) {
stemmer = new swedishStemmer();
}
else if (ALGORITHM.TURKISH.equals(algorithm)) {
stemmer = new turkishStemmer();
}
else {
throw new IllegalStateException("Unexpected stemmer algorithm: " + algorithm.toString());
}
}
public SnowballStemmer(ALGORITHM algorithm) {
this(algorithm, 1);
}
public CharSequence stem(CharSequence word) {
stemmer.setCurrent(word.toString());
for (int i = 0; i < repeat; i++) {
stemmer.stem();
}
return stemmer.getCurrent();
}
}