利用Jackson序列化实现数据脱敏

　　几天前使用了Jackson对数据的自定义序列化。突发灵感，利用此方法来简单实现接口返回数据脱敏，故写此文记录。核心思想是利用Jackson的StdSerializer,@JsonSerialize，以及自己实现的数据脱敏过程。
　　使用效果如下:首先在需要进行脱敏的VO字段上面标注相关脱敏注解
　　调用接口即可看到脱敏效果
　　实现过程如下:1. 定义脱敏的过程实现 /**  * Created by EalenXie on 2021/9/24 15:52  * 顶级的脱敏器  */ public interface Desensitization {      /**      * 脱敏实现      *      * @param target 脱敏对象      * @return 脱敏返回结果      */     T desensitize(T target);  }
　　比如具体的手机号脱敏器实现import com.github.Symbol;  import java.util.regex.Matcher; import java.util.regex.Pattern;  /**  * Created by EalenXie on 2021/9/24 15:56  * 手机号脱敏器 默认只保留前3位和后4位  */ public class PhoneDesensitization implements StringDesensitization {      /**      * 手机号正则      */     private static final Pattern DEFAULT_PATTERN = Pattern.compile(＂(13[0-9]|14[579]|15[0-3,5-9]|16[6]|17[0135678]|18[0-9]|19[89])d{8}＂);      /**      * 手机号脱敏 只保留前3位和后4位      */     @Override     public String desensitize(String target) {         Matcher matcher = DEFAULT_PATTERN.matcher(target);         while (matcher.find()) {             String group = matcher.group();             target = target.replace(group, group.substring(0, 3) + Symbol.getSymbol(4, Symbol.STAR) + group.substring(7, 11));         }         return target;     } } 2.定义脱敏注解,并指明了使用的序列化器,注解中声明了使用的脱敏器实现 package com.github.annotation;  import com.fasterxml.jackson.annotation.JacksonAnnotationsInside; import com.fasterxml.jackson.databind.annotation.JsonSerialize; import com.github.desensitization.Desensitization; import com.github.serializer.ObjectDesensitizeSerializer;  import java.lang.annotation.*;  /**  * Created by EalenXie on 2021/10/8 11:30  */ @Target({ElementType.FIELD, ElementType.ANNOTATION_TYPE}) @Retention(RetentionPolicy.RUNTIME) @JacksonAnnotationsInside @JsonSerialize(using = ObjectDesensitizeSerializer.class) @Documented public @interface Desensitize {     /**      * 脱敏器实现      */     @SuppressWarnings(＂all＂)     Class<? extends Desensitization<?>> desensitization(); }  3. 实现定义的序列化器 import com.fasterxml.jackson.core.JsonGenerator; import com.fasterxml.jackson.databind.BeanProperty; import com.fasterxml.jackson.databind.JsonSerializer; import com.fasterxml.jackson.databind.SerializerProvider; import com.fasterxml.jackson.databind.ser.ContextualSerializer; import com.fasterxml.jackson.databind.ser.std.StdSerializer; import com.github.Symbol; import com.github.annotation.Desensitize; import com.github.desensitization.Desensitization; import com.github.desensitization.DesensitizationFactory; import com.github.desensitization.StringDesensitization;  import java.io.IOException;  /**  * Created by EalenXie on 2021/8/9 9:03  * 脱敏序列化器  */ public class ObjectDesensitizeSerializer extends StdSerializer