如何将数据库中json格式的列值映射到java对象的属性中

mysql5.7版本之后,列值的类型支持json格式,那么如何将json格式的字段类型的值映射到java对象当中呢?以下记录一下转换方法.
数据库展示:

specs列为json格式,现将此列的值映射到java的对象的属性当中
分析json串,需要创建一个VO对象,用于保存json串中的对象

public class Spec implements Serializable {
    private Integer key_id;
    private String key;
    private Integer value_id;
    private String value;
}

创建Pojo对象

@Entity
@Table(name = "sku")
@Getter
@Setter
public class SkuEntity extends baseEntity {
    @Id
    private int id;
    private BigDecimal price;
    private BigDecimal discountPrice;
    private byte online;
    private String img;
    private String title;
    private int spuId;
    //private Listspecs;
    private String specs;
    private String code;
    private int stock;
    private Integer categoryId;
    private Integer rootCategoryId;

GenericAndJson工具类代码:

package com.my.sevencell.api.utils;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.my.sevencell.api.exception.http.ServerErrorException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.io.IOException;


@Component
@Slf4j
public class GenericAndJson {
    private static ObjectMapper mapper;

    
    @Autowired
    public void setMapper(ObjectMapper mapper) {
 GenericAndJson.mapper = mapper;
    }

    public static String objectToJson(T o){
 try {
     String jsonString = mapper.writevalueAsString(o);
     return jsonString;
 } catch (JsonProcessingException e) {
     log.error(e.getMessage());
     throw new ServerErrorException(9999);
 }
    }
    public static T jsonToObject(String json, TypeReferencetypeReference){
 try {
     if (json.isEmpty()){
  return null;
     }
     T t = mapper.readValue(json, typeReference);
     return t;
 } catch (IOException e) {
     log.error(e.getMessage());
     throw new ServerErrorException(9999);
 }
    }
}

   private String specs;
  

 public List getSpecs() {
 if(this.specs.isEmpty()){
     return Collections.emptyList();
 }
 List specs = GenericAndJson.jsonToObject(this.specs, new TypeReference>() {
 });
 return specs;
    }

    public void setSpecs(List specs) {
 String json = GenericAndJson.objectToJson(specs);
 this.specs = json;
    }

{
    "id": 1,
    "price": 3999.00,
    "discount_price": null,
    "online": 1,
    "img": "http://xxxxx",
    "title": "复古双色沙发（藏青色）",
    "spu_id": 1,
    "specs": [
 {
     "key_id": 1,
     "key": "颜色",
     "value_id": 2,
     "value": "藏青色"
 },
 {
     "key_id": 7,
     "key": "双色沙发尺寸（非标）",
     "value_id": 32,
     "value": "1.5米 x 1米"
 }
    ],
    "code": "1$1-2#7-32",
    "stock": 89,
    "category_id": 35,
    "root_category_id": null
}

package com.my.sevencell.api.utils;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.my.sevencell.api.exception.http.ServerErrorException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;

import javax.persistence.AttributeConverter;
import java.io.IOException;


@Slf4j
public class ConveterObjectAndJson implements AttributeConverter {
    @Autowired
    private ObjectMapper objectMapper;
    @Override
    public String convertToDatabaseColumn(T t) {
 try {
     String jsonString = objectMapper.writevalueAsString(t);
     return jsonString;
 } catch (JsonProcessingException e) {
     log.error(e.getMessage());
     throw new ServerErrorException(9999);
 }
    }

    @Override
    public T convertToEntityAttribute(String s) {
 try {
     if(s.isEmpty()){
  return null;
     }
     T t = objectMapper.readValue(s, new TypeReference() {
     });
     return t;
 } catch (IOException e) {
     log.error(e.getMessage());
     throw new ServerErrorException(9999);
 }
    }
}

注意:
1.specs属性的get/set方法可自动生成,无需进行任何改动.
2.用List接收时,idea会报错,不过不影响正常运行,可忽略
3.@Conver是avax.persistence包下的;

@Convert(converter = ConveterObjectAndJson.class)
private List specs;

{
    "id": 1,
    "price": 3999.00,
    "discount_price": null,
    "online": 1,
    "img": "http://xxxx",
    "title": "复古双色沙发（藏青色）",
    "spu_id": 1,
    "specs": [
 {
     "key": "颜色",
     "value": "藏青色",
     "key_id": 1,
     "value_id": 2
 },
 {
     "key": "双色沙发尺寸（非标）",
     "value": "1.5米 x 1米",
     "key_id": 7,
     "value_id": 32
 }
    ],
    "code": "1$1-2#7-32",
    "stock": 89,
    "category_id": 35,
    "root_category_id": null
}