Java实现AES算法

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 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;
    }
}  `