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 * this work for additional information regarding copyright ownership.
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package org.apache.lucene.analysis.synonym;


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.ArrayUtil;
import org.apache.lucene.util.CharsRef;
import org.apache.lucene.util.CharsRefBuilder;

Parser for wordnet prolog format

See http://wordnet.princeton.edu/man/prologdb.5WN.html for a description of the format.

@lucene.experimental
/** * 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.Parser { private final boolean expand; public WordnetSynonymParser(boolean dedup, boolean expand, Analyzer analyzer) { super(dedup, analyzer); this.expand = expand; } @Override public void parse(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; } synset = ArrayUtil.grow(synset, synsetSize + 1); synset[synsetSize] = parseSynonym(line, new CharsRefBuilder()); 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, CharsRefBuilder reuse) throws IOException { if (reuse == null) { reuse = new CharsRefBuilder(); } int start = line.indexOf('\'')+1; int end = line.lastIndexOf('\''); String text = line.substring(start, end).replace("''", "'"); return analyze(text, reuse); } private void addInternal(CharsRef synset[], int size) { 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); } } } }