morfologik-addon/src/main/java/opennlp/morfologik/tagdict/MorfologikTagDictionary.java

/*
 * 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.morfologik.tagdict;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import morfologik.stemming.Dictionary;
import morfologik.stemming.DictionaryLookup;
import morfologik.stemming.IStemmer;
import morfologik.stemming.WordData;
import opennlp.tools.postag.TagDictionary;

/**
 * A POS Tagger dictionary implementation based on Morfologik binary
 * dictionaries
 */
public class MorfologikTagDictionary implements TagDictionary {

  private IStemmer dictLookup;
  private boolean isCaseSensitive;

  /**
   * Creates a case sensitive {@link MorfologikTagDictionary}
   *
   * @param dict
   *          a Morfologik FSA dictionary
   * @throws IllegalArgumentException
   *           if FSA's root node cannot be acquired (dictionary is empty).
   * @throws IOException
   *           could not read dictionary from dictURL
   */
  public MorfologikTagDictionary(Dictionary dict)
      throws IllegalArgumentException, IOException {
    this(dict, true);
  }

  /**
   * Creates MorfologikLemmatizer
   *
   * @param dict
   *          a Morfologik FSA dictionary
   * @param caseSensitive
   *          if true it performs case sensitive lookup
   * @throws IllegalArgumentException
   *           if FSA's root node cannot be acquired (dictionary is empty).
   * @throws IOException
   *           could not read dictionary from dictURL
   */
  public MorfologikTagDictionary(Dictionary dict, boolean caseSensitive)
      throws IllegalArgumentException, IOException {
    this.dictLookup = new DictionaryLookup(dict);
    this.isCaseSensitive = caseSensitive;
  }

  @Override
  public String[] getTags(String word) {
    if (!isCaseSensitive) {
      word = word.toLowerCase();
    }

    List<WordData> data = dictLookup.lookup(word);
    if (data != null && data.size() > 0) {
      List<String> tags = new ArrayList<String>(data.size());
      for (int i = 0; i < data.size(); i++) {
        tags.add(data.get(i).getTag().toString());
      }
      if (tags.size() > 0)
        return tags.toArray(new String[tags.size()]);
      return null;
    }
    return null;
  }
}