jGNatdZd

1KeyGenerator keyGen;
2
3try {
4  keyGen = KeyGenerator.getInstance("AES");
5  keyGen.init(256);
6  SecretKey secretKey = keyGen.generateKey();
7  return secretKey;    
8}
9catch (Exception e) {
10  e.printStackTrace();
11  return null;
12}
13	
14private byte[] aes256Encode(SecretKey key, IvParameterSpec iv, String message) throws InvalidKeyException,
15      InvalidAlgorithmParameterException,
16      NoSuchAlgorithmException, NoSuchPaddingException,
17      IllegalBlockSizeException, BadPaddingException 
18  {
19    Cipher cipher = Cipher.getInstance("AES/CFB/PKCS5Padding");
20    cipher.init(Cipher.ENCRYPT_MODE, key, iv);
21    byte[] encrypted = cipher.doFinal(message.getBytes());
22    return encrypted;
23  }
24	
25private IvParameterSpec generateAESIV() {
26    // build the initialization vector (randomly).
27    SecureRandom random = new SecureRandom();
28    byte iv[] = new byte[16];//generate random 16 byte long
29    random.nextBytes(iv);
30    IvParameterSpec ivspec = new IvParameterSpec(iv);
31    return ivspec;
32  }
33	
34Exception in thread "main" java.security.InvalidKeyException: Illegal key size
35    at javax.crypto.Cipher.checkCryptoPerm(Cipher.java:1039)
36    at javax.crypto.Cipher.implInit(Cipher.java:805)
37    at javax.crypto.Cipher.chooseProvider(Cipher.java:864)
38    at javax.crypto.Cipher.init(Cipher.java:1396)
39    at javax.crypto.Cipher.init(Cipher.java:1327)