Java实现AES算法

　　使用AES算法可用于对数据进行加密码与解密，使用的时候需要注意两点：1）被加密的串越长，加密后的字符串越长，注意数据库字段的设计；2）Linux与Windows环境中可能会出现由于环境差异导致在Windows中测试成功，到Linux上后加密的串无法被正确解密。下列算法已在真实环境中进行实测，应用时也务必做好二次验证避免出现线上事故。

    private static final String ALGORITHM_NAME = "AES";
　　 //加密因子，可根据您的需要自定义
    private static final String DEFAULT_ENCRYPT_RULE = "AES/CBC/PKCS5Padding";
    private static final String RANDOM_KEY_ALGORITHM = "SHA1PRNG";
    private static final String RANDOM_KEY_ALGORITHM_PROVIDER = "SUN";

    /**
     * AES加密
     * @param content 待加密的内容，为空时为回空
     * @return 加密后的base64格式的结果，出现异常时返回null
     */
    public static String encrypt(String content) {
        if (StringUtils.isEmpty(content)) {
            return null;
        }
        try {
            KeyGenerator keyGenerator = KeyGenerator.getInstance(ALGORITHM_NAME);
            SecureRandom secureRandom = SecureRandom.getInstance(RANDOM_KEY_ALGORITHM, RANDOM_KEY_ALGORITHM_PROVIDER);
            secureRandom.setSeed(DEFAULT_ENCRYPT_RULE.getBytes());
            keyGenerator.init(128, secureRandom);
            SecretKey originalKey = keyGenerator.generateKey();
            SecretKey secretKey = new SecretKeySpec(originalKey.getEncoded(), ALGORITHM_NAME);
            Cipher cipher = Cipher.getInstance(ALGORITHM_NAME);
            cipher.init(Cipher.ENCRYPT_MODE, secretKey);
            byte[] encrypted = cipher.doFinal(content.getBytes("utf-8"));
            String result = new String(Base64.getEncoder().encodeToString(encrypted));
            return  result;
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            return null;
        }
    }


    /**
     * 解密
     * @param encrypted 加密后的base64格式的密文
     * @return 解密后的原文，出现异常时返回null
     */
    public static String decrypt(String encrypted) {
        if (StringUtils.isEmpty(encrypted)) {
            return null;
        }
        try {
            KeyGenerator keyGenerator = KeyGenerator.getInstance(ALGORITHM_NAME);
            SecureRandom secureRandom = SecureRandom.getInstance(RANDOM_KEY_ALGORITHM, RANDOM_KEY_ALGORITHM_PROVIDER);
            secureRandom.setSeed(DEFAULT_ENCRYPT_RULE.getBytes());
            keyGenerator.init(128, secureRandom);
            SecretKey originalKey = keyGenerator.generateKey();
            SecretKey secretKey = new SecretKeySpec(originalKey.getEncoded(), ALGORITHM_NAME);
            Cipher cipher = Cipher.getInstance(ALGORITHM_NAME);
            cipher.init(Cipher.DECRYPT_MODE, secretKey);
            byte[] decrypted = cipher.doFinal(Base64.getDecoder().decode(encrypted));
            return new String(decrypted, "utf-8");
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            return null;
        }
    }