Java实现简单的加密，解密实例

水深无声 2022-11-18 02:17 154阅读 0赞

## 一 概述 ##

此例子用于简单的加密解密操作

## 二 自定义规则的MD5加密解密 ##

// MD5加密32位
        public static String MD5(String inStr) {
            MessageDigest md5 = null;
            try {
                md5 = MessageDigest.getInstance("MD5");
            } catch (Exception e) {
                System.out.println(e.toString());
                e.printStackTrace();
                return "";
            }
            char[] charArray = inStr.toCharArray();
            byte[] byteArray = new byte[charArray.length];
    
            for (int i = 0; i < charArray.length; i++)
                byteArray[i] = (byte) charArray[i];
    
            byte[] md5Bytes = md5.digest(byteArray);
    
            StringBuffer hexValue = new StringBuffer();
    
            for (int i = 0; i < md5Bytes.length; i++) {
                int val = ((int) md5Bytes[i]) & 0xff;
                if (val < 16)
                    hexValue.append("0");
                hexValue.append(Integer.toHexString(val));
            }
    
            return hexValue.toString();
        }

加密

// 可逆的加密算法
        public static String encode(String inStr) {
            char[] a = inStr.toCharArray();
            for (int i = 0; i < a.length; i++) {
                a[i] = (char) (a[i] ^ 'p');
            }
            String s = new String(a);
            return s;
        }

解密

// 加密后解密
        public static String decode(String inStr) {
            char[] a = inStr.toCharArray();
            for (int i = 0; i < a.length; i++) {
                a[i] = (char) (a[i] ^ 'p');
            }
            String k = new String(a);
            return k;
        }

## 三 基于JDK的AES加密解密 ##

加密

//加密密钥
        public static final String secret = "QINGSHANKEJIWAYINANDYINGE";
    
        /**
         * @Author zhoucheng
         * @MethodName AESJDKEncode
         * @Param [message, Key]
         * @Date 18:22 2021/4/8
         * @return: byte[]
         * @Version 1.0
         * @Description AES加密
         **/
        public static byte[] AESJDKEncode(String message, String Key) {
    
            try {
                KeyGenerator keyGeneratorEncode = KeyGenerator.getInstance("AES");
    
                keyGeneratorEncode.init(256, new SecureRandom(Key.getBytes(StandardCharsets.UTF_8)));
                SecretKey secretKey = keyGeneratorEncode.generateKey();
                byte[] encode = secretKey.getEncoded();
                SecretKeySpec key = new SecretKeySpec(encode, "AES");
    
                //创建密码器
                Cipher cipher = Cipher.getInstance("AES");
                cipher.init(Cipher.ENCRYPT_MODE, key);
                byte[] result = cipher.doFinal(message.getBytes(StandardCharsets.UTF_8));
                return result;
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

解密

/**
         * @Author zhoucheng
         * @MethodName AESJDKDecode
         * @Param [message, Key]
         * @Date 18:22 2021/4/8
         * @return: byte[]
         * @Version 1.0
         * @Description AES解密
         **/
        public static byte[] AESJDKDecode(byte[] message, String Key) {
    
            try {
                KeyGenerator keyGeneratorDecode = KeyGenerator.getInstance("AES");
    
                keyGeneratorDecode.init(256, new SecureRandom(Key.getBytes(StandardCharsets.UTF_8)));
                SecretKey secretKey = keyGeneratorDecode.generateKey();
                byte[] decode = secretKey.getEncoded();
                SecretKeySpec key = new SecretKeySpec(decode, "AES");
                //创建密码器
                Cipher cipher = Cipher.getInstance("AES");
                cipher.init(Cipher.DECRYPT_MODE, key);
                byte[] result = cipher.doFinal(message);
                return result;
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

byte数组转换成字符串输出

/**
         * @Author zhoucheng
         * @MethodName convertByteToHexString
         * @Param [bytes]
         * @Date 19:11 2021/4/8
         * @return: java.lang.String
         * @Version 1.0
         * @Description 将byte数组转化为16进制字符串
         **/
        public static String convertByteToHexString(byte[] bytes) {
    
            String result = "";
    
            for (int i = 0; i < bytes.length; i++) {
                int temp = bytes[i] & 0xff;
                String tempHex = Integer.toHexString(temp);
                if (tempHex.length() < 2) {
                    result += "0" + tempHex;
                }else {
                    result += tempHex;
                }
            }
            return result;
        }

一些加密方式的自我简单实现。