加密與AES-256 Java

我有這個簡單的代碼，我在互聯網上找到..即時通訊學習這個加密/解密的東西..這段代碼似乎工作正常，但我不明白的東西...爲什麼在「c.doFinal（）」（用於AES-256加密/解密）之後，這個傢伙使用BASE64對該加密值進行編碼/解碼？它僅僅通過使用AES還不夠？加密與AES-256 Java

`private static final String ALGO = "AES"; 
private static final byte[] keyValue = 
new byte[] { 'T', 'h', 'e', 'B', 'e', 's', 't', 'S', 'e', 'c', 'r','e', 't', 'K', 'e', 'y' }; 


public static String encrypt(String Data) throws Exception { 
    Key key = generateKey(); 
    Cipher c = Cipher.getInstance("AES"); 
    c.init(Cipher.ENCRYPT_MODE, key); 
    byte[] encVal = c.doFinal(Data.getBytes()); 
    String encryptedValue = new BASE64Encoder().encode(encVal); 
    return encryptedValue; 
} 

public static String decrypt(String encryptedData) throws Exception { 
    Key key = generateKey(); 
    Cipher c = Cipher.getInstance(ALGO); 
    c.init(Cipher.DECRYPT_MODE, key); 
    byte[] decordedValue = new BASE64Decoder().decodeBuffer(encryptedData); 
    byte[] decValue = c.doFinal(decordedValue); 
    String decryptedValue = new String(decValue); 
    return decryptedValue; 
} 
private static Key generateKey() throws Exception { 
    Key key = new SecretKeySpec(keyValue, ALGO); 
    return key; 
} 

public static void main(String[] args) throws Exception { 

    String data = "SOME TEXT"; 
    String dataEnc = AES.encrypt(data); 
    String dataDec = AES.decrypt(dataEnc); 

    System.out.println("Plain Text : " + data); 
    System.out.println("Encrypted Text : " + dataEnc); 
    System.out.println("Decrypted Text : " + dataDec); 
}`

謝謝!!

來源

2013-08-21 Gerardo agustin Riera

這實際上是使用128位AES而不是256.密鑰是16字節; 16字節*每字節8位= 128位密鑰。 – megaflop