code block for README-0

README-0

public class WordScrambler {

  // 4+ letters, 2+ distinct inners
  // \p{IsLatin} equals [a-zA-ZÀ-ÿ]
  // Range [À-ÿ]: accented letters
  private static final Pattern WORD_REGEX =
    Pattern.compile("\\p{IsLatin}(\\p{IsLatin})\\1*(?!\\1)\\p{IsLatin}\\p{IsLatin}+");

  // Scramble words within text
  public static String
    scrambleWords(String text) {

    // Copy input text to output array
    final var result =
      text.toCharArray();

    // Create randomizer for this run
    final var random = new Random();

    // Examine text looking for matches
    WORD_REGEX.matcher(text).results()
      .forEach(match -> {
        // 2nd letter
        final var start =
          match.start() + 1;
        // Penultimate letter
        final var end = match.end() - 1;
        final var length = end - start;

        do {
          // Shuffle inner letter array
          for (var i = start;i < end;i++){
            // Choose random inner index
            final var rndIdx = start +
              random.nextInt(length);
            // Swap current/random chars
            final var save = result[i];
            result[i] = result[rndIdx];
            result[i] = save;
          }
          // Ensure shuffling took place!
        } while (
            IntStream.range(start, end)
              .allMatch(i ->
                result[i] ==
                  text.charAt(i))
          ); // do/while
      }); // forEach

    // Return scrambled text as string
    return new String(result);
  }
}