byte[] key = nonce.getBytes("UTF-8");
MessageDigest messageDigest = MessageDigest.getInstance("SHA-1");
key = messageDigest.digest(key);
key = Arrays.copyOf(key, 16);
SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
Cipher ecipherSymmetric = Cipher.getInstance("AES");
ecipherSymmetric.init(Cipher.ENCRYPT_MODE, secretKeySpec);