code: /* LanguageTool, a natural language style checker
   * Copyright (C) 2020 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.dev;
  
  import org.jetbrains.annotations.NotNull;
  import org.languagetool.AnalyzedSentence;
  import org.languagetool.AnalyzedTokenReadings;
  import org.languagetool.JLanguageTool;
  import org.languagetool.Languages;
  import org.languagetool.rules.Rule;
  import org.languagetool.rules.spelling.SpellingCheckRule;
  import org.languagetool.tagging.Tagger;
  
  import javax.swing.*;
  import javax.swing.text.BadLocationException;
  import javax.swing.text.EditorKit;
  import java.io.*;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.*;
  import java.util.stream.Collectors;
  
  /**
   * Print words unknown to the spell checker, sorted by number of occurrences.
   */
  public class UnknownWordFinder {
  
    private final Map<String,Integer> unknownWords = new HashMap<>();
    private final Set<String> unknownSpelling = new HashSet<>();
    private final Set<String> unknownTag = new HashSet<>();
  
    private void run(File dir, JLanguageTool lt) throws IOException {
      SpellingCheckRule spellerRule = getSpellingCheckRule(lt);
      Tagger tagger = lt.getLanguage().getTagger();
      List<Path> files = Files.walk(dir.toPath()).filter(Files::isRegularFile).collect(Collectors.toList());
      for (Path file : files) {
        handle(file, lt, spellerRule, tagger);
      }
      printResult(unknownWords);
    }
  
    @NotNull
    private SpellingCheckRule getSpellingCheckRule(JLanguageTool lt) {
      SpellingCheckRule spellerRule = null;
      for (Rule rule : lt.getAllActiveRules()) {
        if (rule.isDictionaryBasedSpellingRule()) {
          if (spellerRule != null) {
            throw new RuntimeException("Found more than one spell rule: " + rule + ", " + spellerRule);
          }
          spellerRule = (SpellingCheckRule) rule;
        }
      }
      if (spellerRule == null) {
        throw new RuntimeException("No speller rule found for " + lt.getLanguage());
      }
      return spellerRule;
    }
  
    private void handle(Path f, JLanguageTool lt, SpellingCheckRule rule, Tagger tagger) throws IOException {
      String text = null;
      if (f.toString().toLowerCase().endsWith(".txt")) {
        List<String> lines = Files.readAllLines(f);
        text = String.join(" ", lines);
      } else if (f.toString().toLowerCase().endsWith(".rtf")) {
        text = getTextFromRtf(f);
      } else {
        System.out.println("Ignoring " + f + ": unknown suffix");
      }
      if (text != null) {
        System.out.println("Working on " + f);
        List<AnalyzedSentence> analyzedSentences = lt.analyzeText(text);
        for (AnalyzedSentence analyzedSentence : analyzedSentences) {
          AnalyzedTokenReadings[] tokens = analyzedSentence.getTokensWithoutWhitespace();
          for (AnalyzedTokenReadings token : tokens) {
            String t = token.getToken();
            boolean misspelled = !t.matches("[\\d%$]+") && rule.isMisspelled(t);
            if (misspelled) {
              unknownSpelling.add(t);
            }
            List<AnalyzedTokenReadings> tags = tagger.tag(Collections.singletonList(t));
            boolean noTag = tags.size() == 1 && !tags.get(0).isTagged() && !t.matches("[\\d%$]+");
            if (noTag) {
              unknownTag.add(t);
            }
            if (misspelled || noTag) {
              if (unknownWords.containsKey(t)) {
                unknownWords.put(t, unknownWords.get(t) + 1);
              } else {
                unknownWords.put(t, 1);
              }
            }
          }
        }
      }
    }
  
    private String getTextFromRtf(Path f) throws IOException {
      JEditorPane p = new JEditorPane();
      p.setContentType("text/rtf");
      EditorKit rtfKit = p.getEditorKitForContentType("text/rtf");
      try {
        rtfKit.read(new FileReader(f.toFile()), p.getDocument(), 0);
        Writer writer = new StringWriter();
        EditorKit txtKit = p.getEditorKitForContentType("text/plain");
        txtKit.write(writer, p.getDocument(), 0, p.getDocument().getLength());
        return  writer.toString();
      } catch (BadLocationException e) {
        System.err.println("Problem running on " + f + ": " + e.getMessage());
        return null;
      }
    }
  
    private void printResult(Map<String, Integer> unknownWords) {
      List<CountedWord> countedWords = new ArrayList<>();
      for (Map.Entry<String, Integer> entry : unknownWords.entrySet()) {
        countedWords.add(new CountedWord(entry.getKey(), entry.getValue()));
      }
      Collections.sort(countedWords);
      System.out.println("== RESULT ==");
      System.out.println("count\tterm\tunknownSpelling\tunknownTag");
      for (CountedWord countedWord : countedWords) {
        String t = countedWord.word;
        System.out.println(countedWord.count + "\t" + t + "\t" + unknownSpelling.contains(t) + "\t" + unknownTag.contains(t));
      }
    }
  
    static class CountedWord implements Comparable<CountedWord> {
      int count;
      String word;
      CountedWord(String key, Integer value) {
        word = key;
        count = value;
      }
      @Override
      public int compareTo(@NotNull CountedWord countedWord) {
        return Integer.compare(countedWord.count, count);
      }
    }
  
    public static void main(String[] args) throws IOException {
      if (args.length != 2) {
        System.out.println("Usage: " + UnknownWordFinder.class.getSimpleName() +  " <langCode> <dir>");
        System.exit(1);
      }
      JLanguageTool lt = new JLanguageTool(Languages.getLanguageForShortCode(args[0]));
      new UnknownWordFinder().run(new File(args[1]), lt);
    }
  }
  