code: String wrap(String toWrap, int len, int start) {
      StringBuilder buff = new StringBuilder();
      StringBuilder line = new StringBuilder();
  
      char[] head = new char[start];
      Arrays.fill(head, ' ');
  
      for (StringTokenizer tok = new StringTokenizer(toWrap, " ");
           tok.hasMoreTokens();) {
        String next = tok.nextToken();
        final int x = line.length();
        line.append(line.length() == 0 ? "" : " ").append(next);
        if (line.length() > len) {
          // The line is now too long. Backtrack: remove the last word, start a
          // new line containing just that word.
          line.setLength(x);
          buff.append(line).append(SEPARATOR).append(head);
          line.setLength(0);
          line.append(next);
        }
      }
  
      buff.append(line);
  
      return buff.toString();
    }
docs: Wrap the specified string by breaking on space characters.
  
  @param toWrap the string to wrap
  @param len    the maximum length of any line
  @param start  the number of spaces to pad at the beginning of a line
  @return the wrapped string