test

    public static BencodeString getString(String source, int index) {
        BencodeString b = null;
        String lengthStr = StringUtils.EMPTY;
        int length = 0;
          try {
        char c = source.charAt(index);
        if(c >= '0' && c <= '9') {
            source = source.substring(index);
            lengthStr = source.split(":")[0];
            length = Integer.parseInt(lengthStr);

            b = new BencodeString(source.substring(lengthStr.length() + 1, lengthStr.length() + 1 + length));
            
        }
          } catch (Exception e) {
              System.out.println("@@@@@@@@@@@:"+source.length());
              System.out.println("@@@@@@@@@@@:"+lengthStr.length() + 1);
              System.out.println("@@@@@@@@@@@:"+lengthStr.length() + 1 + length);
              throw new RuntimeException(e);
          }
      return b;
    }