return doFinal(input, inputOffset, inputLength, output, 0);
return doFinal(new byte[0], 0, 0);
  public final int doFinal(byte[] input, int inputOffset, int inputLength,                           byte[] output)    throws IllegalStateException, IllegalBlockSizeException, BadPaddingException,           ShortBufferException  {    return doFinal(input, inputOffset, inputLength, output, 0);  }