// 反例：直接將生產(chǎn)數(shù)據(jù)同步到測(cè)試環(huán)境  
public void syncUserToTest(User user) {  
    testDB.insert(user); // 包含手機(jī)號(hào)、身份證等敏感字段  
}

public class StringMasker {  
    // 手機(jī)號(hào)脫敏：13812345678 → 138****5678  
    public static String maskMobile(String mobile) {  
        return mobile.replaceAll("(\\d{3})\\d{4}(\\d{4})", "$1****$2");  
    }  

    // 身份證脫敏：110101199003077777 → 1101********7777  
    public static String maskIdCard(String idCard) {  
        if (idCard.length() == 18) {  
            return idCard.replaceAll("(\\d{4})\\d{10}(\\w{4})", "$1****$2");  
        }  
        return idCard; // 處理15位舊身份證  
    }  
}

public class AESEncryptor {  
    private static final String ALGORITHM = "AES/GCM/NoPadding";  
    private static final int TAG_LENGTH = 128; // 認(rèn)證標(biāo)簽長(zhǎng)度  

    public static String encrypt(String plaintext, SecretKey key) {  
        byte[] iv = new byte[12]; // GCM推薦12字節(jié)IV  
        SecureRandom random = new SecureRandom();  
        random.nextBytes(iv);  

        Cipher cipher = Cipher.getInstance(ALGORITHM);  
        cipher.init(Cipher.ENCRYPT_MODE, key, new GCMParameterSpec(TAG_LENGTH, iv));  

        byte[] ciphertext = cipher.doFinal(plaintext.getBytes(StandardCharsets.UTF_8));  
        return Base64.getEncoder().encodeToString(iv) + ":" +  
               Base64.getEncoder().encodeToString(ciphertext);  
    }  

    // 解密方法類似...  
}

-- 創(chuàng)建脫敏視圖  
CREATE VIEW masked_customers AS  
SELECT  
    id,  
    CONCAT(SUBSTR(name,1,1), '***') AS name,  
    CONCAT(SUBSTR(mobile,1,3), '****', SUBSTR(mobile,8,4)) AS mobile  
FROM customers;  

-- 使用列級(jí)權(quán)限控制  
GRANT SELECT (id, name, mobile) ON masked_customers TO test_user;

rules:  
- !MASK  
  tables:  
    user:  
      columns:  
        phone:  
          maskAlgorithm: phone_mask  
  maskAlgorithms:  
    phone_mask:  
      type: MD5  
      props:  
        salt: abcdefg123456

// 使用Guava Cache實(shí)現(xiàn)LRU緩存  
LoadingCache<String, String> dataMapping = CacheBuilder.newBuilder()  
    .maximumSize(100000)  
    .expireAfterAccess(30, TimeUnit.MINUTES)  
    .build(new CacheLoader<String, String>() {  
        public String load(String key) {  
            return UUID.randomUUID().toString().replace("-", "");  
        }  
    });  

public String replaceData(String original) {  
    return dataMapping.get(original);  
}

@Aspect  
@Component  
public class DataMaskAspect {  

    @Around("@annotation(requiresMasking)")  
    public Object maskData(ProceedingJoinPoint joinPoint, RequiresMasking requiresMasking) throws Throwable {  
        Object result = joinPoint.proceed();  
        return mask(result, requiresMasking.type());  
    }  

    private Object mask(Object data, MaskType type) {  
        if (data instanceof User) {  
            User user = (User) data;  
            switch(type) {  
                case MOBILE:  
                    user.setMobile(MaskUtil.maskMobile(user.getMobile()));  
                    break;  
                case ID_CARD:  
                    user.setIdCard(MaskUtil.maskIdCard(user.getIdCard()));  
                    break;  
            }  
        }  
        return data;  
    }  
}

public class KAnonymity {  

    // 年齡泛化：精確值→范圍  
    public static String generalizeAge(int age) {  
        int range = 10; // K=10  
        int lower = (age / range) * range;  
        int upper = lower + range - 1;  
        return lower + "-" + upper;  
    }  
}