### Question:
EncryptionService { public byte[] decryptData(byte[] encryptedData) { try { Cipher cipher = Cipher.getInstance("AES"); cipher.init(Cipher.DECRYPT_MODE, getAesKey()); return cipher.doFinal(encryptedData); } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | IllegalBlockSizeException | BadPaddingException ex) { throw new SecurityException(ex); } } EncryptionService(); byte[] encryptData(byte[] data); byte[] decryptData(byte[] encryptedData); Key getAesKey();  }### Answer:
@Test public void decryptData() throws Exception { final String base64Encoded = "hfZcGLKmy9Q9iPRR+3XfmV7TzHoYU+6NKvJk4gSZfI0="; EncryptionService cut = new EncryptionService(); cut.encryptionKey = createEncryptionKey("01234567890123456789012345678912"); assertThat(new String(cut.decryptData(Base64.getDecoder().decode(base64Encoded))), Is.is("test@example.com")); }