private String[] sample(String[] words, int wordsCount) {
    int len = words.length;
    int iterations = Math.min(len, wordsCount);
    Set<String> result = new TreeSet<>();
    while (result.size() < iterations) {
      int i = rand(0, len - 1);
      result.add(words[i]);
    }

    return ArrayUtilRt.toStringArray(result);
  }
private String[] sample(String[] words, int wordsCount)