DES加密、Base64加密\File文件相互转换

注意：DES加密和解密过程中，密钥长度都必须是8的倍数

/**

     * 加密
     *
     * @param datasource byte[]
     * @param password   String
     * @return byte[]
     */
    public static byte[] encrypt(byte[] datasource, byte[] password) {
        try {
            SecureRandom random = new SecureRandom();
            DESKeySpec desKey = new DESKeySpec(password);
            //创建一个密匙工厂，然后用它把DESKeySpec转换成
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey securekey = keyFactory.generateSecret(desKey);
            //Cipher对象实际完成加密操作
            Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
            //用密匙初始化Cipher对象
            cipher.init(Cipher.ENCRYPT_MODE, securekey);
            //现在，获取数据并加密
            //正式执行加密操作
            return cipher.doFinal(datasource);
        } catch (Throwable e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 解密
     *
     * @param src      byte[]
     * @param password String
     * @return byte[]
     * @throws Exception
     */
    public static byte[] decrypt(byte[] src, byte[] password) {
        // 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 = null;
        try {
            desKey = new DESKeySpec(password);
            // 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/ECB/PKCS5Padding");//NoPadding
            // 用密匙初始化Cipher对象
            cipher.init(Cipher.DECRYPT_MODE, securekey);
            // 真正开始解密操作
            return cipher.doFinal(src);
        } catch (Exception e) {
            throw new RuntimeException(e);
           
        }
    }

    /**
     * 将 16 进制字符串转换成 16 进制数字数组
     * 在密钥传输交换阶段,使用DES进行加解密前需要调用以下方法对DES的密钥进行转 换,即转换后的才是正真的密钥。
     */

    public static byte[] asc2bin(String hexString) {
        byte[] hexbyte = hexString.getBytes();
        byte[] bitmap = new byte[hexbyte.length / 2];
        for (int i = 0; i < bitmap.length; i++) {
            hexbyte[i * 2] -= hexbyte[i * 2] > '9' ? 7 : 0;
            hexbyte[i * 2 + 1] -= hexbyte[i * 2 + 1] > '9' ? 7 : 0;
            bitmap[i] = (byte) ((hexbyte[i * 2] << 4 & 0xf0) | (hexbyte[i * 2 + 1] & 0x0f));
        }
        return bitmap;
    }

    /**
     * 把 16 进制数字数组换成16进制字符串
     */
    public static final String bytesToHexString(byte[] bArray) {
        StringBuffer sb = new StringBuffer(bArray.length);
        String sTemp;
        for (int i = 0; i < bArray.length; i++) {
            sTemp = Integer.toHexString(0xFF & bArray[i]);
            if (sTemp.length() < 2)
                sb.append(0);
            sb.append(sTemp.toUpperCase());
        }
        return sb.toString();
    }
    
    /**
     * BASE64 解密
     *
     * @param key 需要解密的字符串
     * @return 字节数组
     * @throws Exception
     */
    public static byte[] decryptBase64(String key) throws Exception {
        return (new BASE64Decoder()).decodeBuffer(key);
    }

    /**
     * BASE64 加密
     *
     * @param key 需要加密的字节数组
     * @return 字符串
     * @throws Exception
     */
    public static String encryptBase64(byte[] key) throws Exception {
        return (new BASE64Encoder()) .encodeBuffer(key);
    }
    /**将 file 转化为 Base64
     * @throws Exception */  
    public static String fileToBase64(File file) throws Exception {  
        FileInputStream inputFile = new FileInputStream(file);  
        byte[] buffer = new byte[(int) file.length()];  
        inputFile.read(buffer);  
        inputFile.close();  
        return encryptBase64(buffer);  
    }  
    /**将Base64 转换为file文件
     * @throws FileNotFoundException */  
    public static boolean base64ToFile(String base64, File file) throws Exception {  
        byte[] buffer = decryptBase64(base64);  
        FileOutputStream out = new FileOutputStream(file);  
        out.write(buffer);  
        out.close();  
        return true;  
    }