content: package org.apache.lucene.analysis.synonym;
  
  /**
   * 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.
   */
  
  import java.io.IOException;
  import java.io.LineNumberReader;
  import java.io.Reader;
  import java.text.ParseException;
  
  import org.apache.lucene.analysis.Analyzer;
  import org.apache.lucene.util.CharsRef;
  
  /**
   * Parser for wordnet prolog format
   * <p>
   * See http://wordnet.princeton.edu/man/prologdb.5WN.html for a description of the format.
   * @lucene.experimental
   */
  // TODO: allow you to specify syntactic categories (e.g. just nouns, etc)
  public class WordnetSynonymParser extends SynonymMap.Builder {
    private final boolean expand;
    private final Analyzer analyzer;
    
    public WordnetSynonymParser(boolean dedup, boolean expand, Analyzer analyzer) {
      super(dedup);
      this.expand = expand;
      this.analyzer = analyzer;
    }
    
    public void add(Reader in) throws IOException, ParseException {
      LineNumberReader br = new LineNumberReader(in);
      try {
        String line = null;
        String lastSynSetID = "";
        CharsRef synset[] = new CharsRef[8];
        int synsetSize = 0;
        
        while ((line = br.readLine()) != null) {
          String synSetID = line.substring(2, 11);
  
          if (!synSetID.equals(lastSynSetID)) {
            addInternal(synset, synsetSize);
            synsetSize = 0;
          }
  
          if (synset.length <= synsetSize+1) {
            CharsRef larger[] = new CharsRef[synset.length * 2];
            System.arraycopy(synset, 0, larger, 0, synsetSize);
            synset = larger;
          }
          
          synset[synsetSize] = parseSynonym(line, synset[synsetSize]);
          synsetSize++;
          lastSynSetID = synSetID;
        }
        
        // final synset in the file
        addInternal(synset, synsetSize);
      } catch (IllegalArgumentException e) {
        ParseException ex = new ParseException("Invalid synonym rule at line " + br.getLineNumber(), 0);
        ex.initCause(e);
        throw ex;
      } finally {
        br.close();
      }
    }
   
    private CharsRef parseSynonym(String line, CharsRef reuse) throws IOException {
      if (reuse == null) {
        reuse = new CharsRef(8);
      }
      
      int start = line.indexOf('\'')+1;
      int end = line.lastIndexOf('\'');
      
      String text = line.substring(start, end).replace("''", "'");
      return analyze(analyzer, text, reuse);
    }
    
    private void addInternal(CharsRef synset[], int size) throws IOException {
      if (size <= 1) {
        return; // nothing to do
      }
      
      if (expand) {
        for (int i = 0; i < size; i++) {
          for (int j = 0; j < size; j++) {
            add(synset[i], synset[j], false);
          }
        }
      } else {
        for (int i = 0; i < size; i++) {
          add(synset[i], synset[0], false);
        }
      }
    }
  }
  