code: /* LanguageTool, a natural language style checker 
   * Copyright (C) 2014 Daniel Naber (http://www.danielnaber.de)
   * 
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
   * USA
   */
  package org.languagetool.languagemodel;
  
  import org.languagetool.rules.ngrams.Probability;
  
  import java.util.List;
  
  /**
   * A language model that provides information about ngram probabilities.
   * The implementations don't necessarily deal well with the occurrence = 0 case.
   * @since 2.7
   */
  public interface LanguageModel extends AutoCloseable {
    
    /** ngram sentence start marker - note: this is not in the v1 data from Google */
    String GOOGLE_SENTENCE_START = "_START_";
    /** ngram sentence end marker - note: this is not in the v1 data from Google */
    String GOOGLE_SENTENCE_END = "_END_";
  
    /** 
     * This is not always guaranteed to be a real probability (0.0 to 1.0).
     * Throws exception if context is longer than the ngram index supports. 
     * @since 3.2
     */
    Probability getPseudoProbability(List<String> context);
  
    @Override
    void close();
    
  }
  