/* LanguageTool, a natural language style checker
* Copyright (C) 2009 Marcin Miłkowski
*
* 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.synthesis;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import morfologik.stemming.Dictionary;
import morfologik.stemming.DictionaryLookup;
import morfologik.stemming.IStemmer;
import morfologik.stemming.WordData;
import org.languagetool.AnalyzedToken;
import org.languagetool.JLanguageTool;
public class BaseSynthesizer implements Synthesizer {
protected volatile List<String> possibleTags;
private final String tagFileName;
private final String resourceFileName;
private final IStemmer stemmer;
private volatile Dictionary dictionary;
/**
* @param resourceFileName The dictionary file name.
* @param tagFileName The name of a file containing all possible tags.
*/
public BaseSynthesizer(final String resourceFileName, final String tagFileName) {
this.resourceFileName = resourceFileName;
this.tagFileName = tagFileName;
this.stemmer = createStemmer();
}
/**
* Returns the {@link Dictionary} used for this synthesizer.
* The dictionary file can be defined in the {@link #BaseSynthesizer(String, String) constructor}.
*
* @throws IOException In case the dictionary cannot be loaded.
*/
protected Dictionary getDictionary() throws IOException {
Dictionary dict = this.dictionary;
if (dict == null) {
synchronized (this) {
dict = this.dictionary;
if (dict == null) {
final URL url = JLanguageTool.getDataBroker().getFromResourceDirAsUrl(resourceFileName);
this.dictionary = dict = Dictionary.read(url);
}
}
}
return dict;
}
/**
* Creates a new {@link IStemmer} based on the configured {@link #getDictionary() dictionary}.
* The result must not be shared among threads.
*
* @since 2.3
*/
protected IStemmer createStemmer() {
try {
final Dictionary dict = getDictionary();
return new DictionaryLookup(dict);
} catch (IOException e) {
throw new RuntimeException("Could not load dictionary", e);
}
}
/**
* Lookup the inflected forms of a lemma defined by a part-of-speech tag.
* @param lemma the lemma to be inflected.
* @param posTag the desired part-of-speech tag.
* @param results the list to collect the inflected forms.
*/
protected void lookup(String lemma, String posTag, List<String> results) {
synchronized (this) { // the stemmer is not thread-safe
final List<WordData> wordForms = stemmer.lookup(lemma + "|" + posTag);
for (WordData wd : wordForms) {
results.add(wd.getStem().toString());
}
}
}
/**
* Get a form of a given AnalyzedToken, where the form is defined by a
* part-of-speech tag.
*
* @param token AnalyzedToken to be inflected.
* @param posTag The desired part-of-speech tag.
* @return inflected words, or an empty array if no forms were found
*/
@Override
public String[] synthesize(final AnalyzedToken token, final String posTag) throws IOException {
final List<String> wordForms = new ArrayList<>();
lookup(token.getLemma(), posTag, wordForms);
return wordForms.toArray(new String[wordForms.size()]);
}
@Override
public String[] synthesize(final AnalyzedToken token, final String posTag,
final boolean posTagRegExp) throws IOException {
if (posTagRegExp) {
initPossibleTags();
final Pattern p = Pattern.compile(posTag);
final List<String> results = new ArrayList<>();
for (final String tag : possibleTags) {
final Matcher m = p.matcher(tag);
if (m.matches()) {
lookup(token.getLemma(), tag, results);
}
}
return results.toArray(new String[results.size()]);
}
return synthesize(token, posTag);
}
@Override
public String getPosTagCorrection(final String posTag) {
return posTag;
}
/**
* @since 2.5
*
* @return the stemmer interface to be used.
*/
public IStemmer getStemmer() {
return stemmer;
}
protected void initPossibleTags() throws IOException {
List<String> tags = possibleTags;
if (tags == null) {
synchronized (this) {
tags = possibleTags;
if (tags == null) {
possibleTags = SynthesizerTools.loadWords(JLanguageTool.getDataBroker().getFromResourceDirAsStream(tagFileName));
}
}
}
}
}