DES加密和解密

    //DES是加密方式 CBC是工作模式 PKCS5Padding是填充模式
    private final static String TRANSFORMATION = "DES/CBC/PKCS5Padding";
    //初始化向量参数，AES 为16bytes. DES 为8bytes.
    private final static byte[] IVPARAMETERSPEC = {0,0,0,0,0,0,0,0};  
    //DES是加密方式
    private final static String ALGORITHM = "DES";

    /**
     * DES算法，加密
     *
     * @param data 待加密字符串
     * @param key  加密私钥，长度不能够小于8位
     * @return 加密后的字节数组，一般结合Base64编码使用
     */
    public static String encode(String key, byte[] data) {
        try {
            Cipher cipher = Cipher.getInstance(TRANSFORMATION);
            IvParameterSpec iv = new IvParameterSpec(IVPARAMETERSPEC);
            cipher.init(Cipher.ENCRYPT_MODE, getRawKey(key), iv);
            byte[] bytes = cipher.doFinal(data);
            return bytes2HexString(bytes);
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * 字节数组转16进制字符串;
     * @param array 数组
     * @return string
     */
    private static String bytes2HexString(byte[] array) {
        StringBuilder builder = new StringBuilder();

        for (byte b : array) {
            String hex = Integer.toHexString(b & 0xFF);
            if (hex.length() == 1) {
                hex = '0' + hex;
            }
            builder.append(hex);
        }

        return builder.toString().toUpperCase();
    }
    // 对密钥进行处理
    private static Key getRawKey(String key) throws Exception {
        DESKeySpec dks = new DESKeySpec(key.getBytes());
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(ALGORITHM);
        return keyFactory.generateSecret(dks);
    }

   /**
     * 解密
     *
     */

    public static byte[] decrypt(byte[] src, String password) throws Exception {

        // DES算法要求有一个可信任的随机数源
        SecureRandom random = new SecureRandom();
        // 创建一个DESKeySpec对象
        DESKeySpec desKey = new DESKeySpec(password.getBytes());
        // 创建一个密匙工厂
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        // 将DESKeySpec对象转换成SecretKey对象
        SecretKey securekey = keyFactory.generateSecret(desKey);
        // Cipher对象实际完成解密操作
        Cipher cipher = Cipher.getInstance("DES");
        // 用密匙初始化Cipher对象
        cipher.init(Cipher.DECRYPT_MODE, securekey, random);
        // 真正开始解密操作
        return cipher.doFinal(src);
    }