code: public static PTBTokenizer<Word> newPTBTokenizer(Reader r, boolean tokenizeNLs) {
      return new PTBTokenizer<Word>(r, tokenizeNLs, false, false, new WordTokenFactory());
    }
docs: Constructs a new PTBTokenizer that optionally returns newlines
  as their own token. NLs come back as Words whose text is
  the value of <code>PTBLexer.NEWLINE_TOKEN</code>.
  
  @param r The Reader to read tokens from
  @param tokenizeNLs Whether to return newlines as separate tokens
  (otherwise they normally disappear as whitespace)
  @return A PTBTokenizer which returns Word tokens