场景

SpringBoot中整合Sharding Sphere实现数据加解密/数据脱敏/数据库密文，查询明文：

https://blog.csdn.net/BADAO_LIUMANG_QIZHI/article/details/131742091

上面讲的是数据库中存储密文，查询时使用明文的脱敏方式，如果是需要数据库中存储

明文，而在查询时返回处理后的数据，比如身份证号、手机号等敏感数据，可以通过如下方式。

注：

博客：
https://blog.csdn.net/badao_liumang_qizhi

实现

1、自定义Jackson注解

import com.fasterxml.jackson.annotation.JacksonAnnotationsInside;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.FIELD)
@JacksonAnnotationsInside
@JsonSerialize(using = SensitiveJsonSerializer.class)
public @interface Sensitive {
    //脱敏策略
    SensitiveStrategy strategy();
}

2、指定脱敏策略，这个规则根据业务具体需求去制定，下面只做演示

import java.util.function.Function;

/**
 * 脱敏策略，枚举类，针对不同的数据定制特定的策略
 */
public enum SensitiveStrategy {
    /**
     * 用户名
     */
    USERNAME(s -> s.replaceAll("(\\S)\\S(\\S*)", "$1*$2")),
    /**
     * 身份证
     */
    ID_CARD(s -> s.replaceAll("(\\d{4})\\d{10}(\\w{4})", "$1****$2")),
    /**
     * 手机号
     */
    PHONE(s -> s.replaceAll("(\\d{3})\\d{4}(\\d{4})", "$1****$2")),
    /**
     * 地址
     */
    ADDRESS(s -> s.replaceAll("(\\S{3})\\S{2}(\\S*)\\S{2}", "$1****$2****"));

    private final Function<String, String> desensitizer;
    SensitiveStrategy(Function<String, String> desensitizer) {
        this.desensitizer = desensitizer;
    }
    public Function<String, String> desensitizer() {
        return desensitizer;
    }
}

3、定制JSON序列化实现

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.BeanProperty;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.ser.ContextualSerializer;
import java.io.IOException;
import java.util.Objects;

/**
 * 序列化注解自定义实现
 * JsonSerializer<String>：指定String 类型，serialize()方法用于将修改后的数据载入
 */
public class SensitiveJsonSerializer extends JsonSerializer<String> implements ContextualSerializer {
    private SensitiveStrategy strategy;
    @Override
    public void serialize(String value, JsonGenerator gen, SerializerProvider serializers) throws
            IOException {
        gen.writeString(strategy.desensitizer().apply(value));
    }
    /**
     * 获取属性上的注解属性
     */
    @Override
    public JsonSerializer<?> createContextual(SerializerProvider prov, BeanProperty property) throws
            JsonMappingException {
        Sensitive annotation = property.getAnnotation(Sensitive.class);
        if (Objects.nonNull(annotation)&&Objects.equals(String.class,
                property.getType().getRawClass())) {
            this.strategy = annotation.strategy();
            return this;
        }
        return prov.findValueSerializer(property.getType(), property);
    }
}

4、新增User类，并对需要脱敏的字段添加注解，并指定脱敏策略

import com.badao.demo.sensitive.Sensitive;
import com.badao.demo.sensitive.SensitiveStrategy;
import lombok.Data;
import java.io.Serializable;

@Data
public class User implements Serializable {

    private static final long serialVersionUID = -5514139686858156155L;

    private Integer id;

    private Integer userId;

    @Sensitive(strategy = SensitiveStrategy.USERNAME)
    private String name;

    private Integer age;

}

5、编写controller进行测试

@RequestMapping("user")
@RestController
public class UserController {

    @Autowired
    private UserService userService;

    @RequestMapping("save")
    public String save() {
        User user = new User();
        user.setUserId(new Random().nextInt( 1000 ) + 1);
        user.setName("badao"+user.getUserId());
        user.setAge(new Random().nextInt( 80 ) + 1);
        userService.insert(user);
        return "save success";
    }

    @RequestMapping("select")
    public User select() {
        List<User> all = userService.findAll();
        return all.size()>0?all.get(0):new User();
    }
}

测试效果