聊聊、AES 和 DES

AES 和 DES 都是对称加密的一种，但是 DES 的 Key 是 56 位，而 AES 的 Key 有 128,256,512 可选。

AES

---

加密AES

String randomKey = "12345678";    

public static String ENAES() {
        try {
            KeyGenerator keyGene = KeyGenerator.getInstance("AES");
            keyGene.init(128, new SecureRandom(randomKey.getBytes()));
            SecretKey key = keyGene.generateKey();
            byte[] bytes = key.getEncoded();
            SecretKeySpec keySpec = new SecretKeySpec(bytes, "AES");
            Cipher ciper = Cipher.getInstance("AES");
            ciper.init(Cipher.ENCRYPT_MODE, keySpec);

            bytes = ciper.doFinal("hello".getBytes());
            String result = org.apache.commons.codec.binary.Base64.encodeBase64String(bytes);
            return result;
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        } catch (BadPaddingException e) {
            e.printStackTrace();
        }
          return null;
    }

解密AES

String randomKey = "12345678";    

  public static String DEAES(String str) {
        try {
            byte[] srcBytes = org.apache.commons.codec.binary.Base64
                    .decodeBase64(str);
            KeyGenerator keyGene = KeyGenerator.getInstance("AES");
            keyGene.init(128, new SecureRandom(randomKey.getBytes()));
            SecretKey key = keyGene.generateKey();
            byte[] bytes = key.getEncoded();
            SecretKeySpec keySpec = new SecretKeySpec(bytes, "AES");
            Cipher ciper = Cipher.getInstance("AES");
            ciper.init(Cipher.DECRYPT_MODE, keySpec);

            bytes = ciper.doFinal(srcBytes);
            String strs = new String(bytes);

            return strs;
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        } catch (BadPaddingException e) {
            e.printStackTrace();
        }
        return null;
    }

 DES

---

加密DES

String randomKey = "12345678";    

public static String ENDES() {
        SecureRandom random = new SecureRandom();
        try {
            DESKeySpec desKey = new DESKeySpec(randomKey.getBytes());
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey securekey = keyFactory.generateSecret(desKey);
            Cipher cipher = Cipher.getInstance("DES");
            cipher.init(Cipher.ENCRYPT_MODE, securekey, random);
            byte[] bytes = cipher.doFinal("hello".getBytes());

            String result = Base64.getEncoder().encodeToString(bytes);
            return result;
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (InvalidKeySpecException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        } catch (BadPaddingException e) {
            e.printStackTrace();
        }
        return null;
    }

解密DES

String randomKey = "12345678"; 

public static String DEDES(String str) {
        byte[] bytes = Base64.getDecoder().decode(str);
        SecureRandom random = new SecureRandom();
        try {
            DESKeySpec desKey = new DESKeySpec(randomKey.getBytes());
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey securekey = keyFactory.generateSecret(desKey);
            Cipher cipher = Cipher.getInstance("DES");
            cipher.init(Cipher.DECRYPT_MODE, securekey, random);
            bytes = cipher.doFinal(bytes);
            String result = new String(bytes);
            return result;
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (InvalidKeySpecException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        } catch (BadPaddingException e) {
            e.printStackTrace();
        }
        return null;
    }

mian 方法

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

        System.out.println("AES ENCRYPT:" + ENAES());
        System.out.println("AES DECRYPT:" + DEAES(ENAES()));
        System.out.println("DES ENCRYPT:" + ENDES());
        System.out.println("DES DECRYPT:" + DEDES(ENDES()));

} 

运行结果

AES ENCRYPT:70IScgmG93zMpkKvsNs+TQ==
AES DECRYPT:hello
DES ENCRYPT:uhbGoCVxJa8=
DES DECRYPT:hello