java des加密解密

Posted 2020-11-21 冷暖自知~~~

public class Des {

    /**
     * 对给定的字符串以指定的编码方式和密钥进行加密
     * @param srcStr 待加密的字符串
     * @param charset 字符集，如utf8
     * @param sKey 密钥 
     */
    public static String encrypt(String srcStr, Charset charset, String sKey) {
        byte[] src = srcStr.getBytes(charset);
        byte[] buf = Des.encrypt(src, sKey);
        return Des.parseByte2HexStr(buf);
    }

    /**
     * 对给定的密文以指定的编码方式和密钥进行解密
     * @param hexStr 需要解密的密文
     * @param charset 字符集
     * @param sKey 密钥
     * @return 解密后的原文
     * @throws Exception
     */
    public static String decrypt(String hexStr, Charset charset, String sKey) throws Exception {
        byte[] src = Des.parseHexStr2Byte(hexStr);
        byte[] buf = Des.decrypt(src, sKey);
        return new String(buf, charset);
    }

    public static byte[] encrypt(byte[] data, String sKey) {
        try {
            byte[] key = sKey.getBytes();

            IvParameterSpec iv = new IvParameterSpec(key);
            DESKeySpec desKey = new DESKeySpec(key);

            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey securekey = keyFactory.generateSecret(desKey);

            Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");

            cipher.init(Cipher.ENCRYPT_MODE, securekey, iv);

            return cipher.doFinal(data);
        } catch (Throwable e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 解密
     * @param src
     * @param sKey
     * @return
     * @throws Exception
     */
    public static byte[] decrypt(byte[] src, String sKey) throws Exception {
        byte[] key = sKey.getBytes();
        // 初始化向量
        IvParameterSpec iv = new IvParameterSpec(key);
        // 创建一个DESKeySpec对象
        DESKeySpec desKey = new DESKeySpec(key);
        // 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/CBC/PKCS5Padding");
        // 用密匙初始化Cipher对象
        cipher.init(Cipher.DECRYPT_MODE, securekey, iv);
        // 真正开始解密操作
        return cipher.doFinal(src);
    }

    /**
     * 将二进制转换成16进制
     *
     * @param buf
     * @return
     */
    public static String parseByte2HexStr(byte buf[]) {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < buf.length; i++) {
            String hex = Integer.toHexString(buf[i] & 0xFF);
            if (hex.length() == 1) {
                hex = \'0\' + hex;
            }
            sb.append(hex.toUpperCase());
        }
        return sb.toString();
    }

    /**
     * 将16进制转换为二进制
     *
     * @param hexStr
     * @return
     */
    public static byte[] parseHexStr2Byte(String hexStr) {
        if (hexStr.length() < 1) return null;
        byte[] result = new byte[hexStr.length() / 2];
        for (int i = 0; i < hexStr.length() / 2; i++) {
            int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16);
            int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2), 16);
            result[i] = (byte) (high * 16 + low);
        }
        return result;
    }
}
 

使用：

    @RequestMapping("/encode")
    public String encode(String data){
        return Des.encrypt(data, Charset.forName("utf8"), "testtest");
    }
    
    @RequestMapping("/decode")
    public String decode(String data) throws Exception{
        return Des.decrypt(data, Charset.forName("utf8"), "testtest");
    }

这里在sprint boot 的controller里使用，这不是重点，重点就是：

Des.encrypt(data, Charset.forName("utf8"), "testtest");

Des.decrypt(data, Charset.forName("utf8"), "testtest");

以上两个方法的调用。

 

参考自：https://www.cnblogs.com/james0/p/7063941.html