nlp-utils/src/main/java/org/apache/opennlp/utils/languagemodel/NoisyChannel.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 org.apache.opennlp.utils.languagemodel;

/**
 * Abstract impl of a noisy channel
 */
public abstract class NoisyChannel {

  private String[] dictionary;

  public void initializeDictionary(String[] dictionary) {
    this.dictionary = dictionary;
  }

  public String findCorrection(String mispelledWord) {
    Double val = 0d;
    String correctWord = null;
    for (String word : dictionary) {
      Double curVal = calculateLikelihood(mispelledWord, word) * calculatePrior(word);
      if (curVal > val) {
        val = curVal;
        correctWord = word;
      }
    }
    return correctWord;
  }

  public abstract Double calculatePrior(String word);

  public abstract Double calculateLikelihood(String misspelledWord, String word);

}