docs: private Object getNext(String txt, String originalText) {
      if (invertible) {
        String str = prevWordAfter.toString();
        prevWordAfter.setLength(0);
        CoreLabel word = (CoreLabel) tokenFactory.makeToken(txt, yychar, yylength());
        word.set(OriginalTextAnnotation.class, originalText);
        word.set(BeforeAnnotation.class, str);
        prevWord.set(AfterAnnotation.class, str);
        prevWord = word;
        return word;
      } else {
        return tokenFactory.makeToken(txt, yychar, yylength());
     }
    }