SpringBoot集成MyBatis操作MySql8的JSON类型

1.定义Json类型转换器：JsonTypeHandler

一个包有一个类型转换器就够了
开箱即用，复制即可

package com.ins.iot.sync.server.handle;import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;public class JsonTypeHandler<T extends Object> extends BaseTypeHandler<T> {private static final ObjectMapper mapper = new ObjectMapper();private Class<T> clazz;public JsonTypeHandler(Class<T> clazz) {if (clazz == null) throw new IllegalArgumentException("Type argument cannot be null");this.clazz = clazz;}@Overridepublic void setNonNullParameter(PreparedStatement ps, int i, T parameter, JdbcType jdbcType) throws SQLException {ps.setString(i, this.toJson(parameter));}@Overridepublic T getNullableResult(ResultSet rs, String columnName) throws SQLException {return this.toObject(rs.getString(columnName), clazz);}@Overridepublic T getNullableResult(ResultSet rs, int columnIndex) throws SQLException {return this.toObject(rs.getString(columnIndex), clazz);}@Overridepublic T getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {return this.toObject(cs.getString(columnIndex), clazz);}private String toJson(T object) {try {return mapper.writeValueAsString(object);} catch (Exception e) {throw new RuntimeException(e);}}private T toObject(String content, Class<?> clazz) {if (content != null && !content.isEmpty()) {try {return (T) mapper.readValue(content, clazz);} catch (Exception e) {throw new RuntimeException(e);}} else {return null;}}static {//mapper.configure(SerializationFeature.WRITE_NULL_MAP_VALUES, false);mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);}
}

2.使用Json类型转换器：JsonTypeHandler

entity: 使用JSONObject类型

@Data
@NoArgsConstructor
public class Org {private Long orgId@ApiModelProperty(value = "参数信息")private JSONObject paramInfo;}

mapper

JSONObject 保存到MySql数据库的 json字段
数据库的 json字段取出并转化成 JSONObject

<mapper namespace="com.xxx.xxx.xxx.mapper.OrgMapper"><insert id="insertBatch" parameterType="java.util.List">insert into org (orgid，,paraminfo)values<foreach collection="list" item="org" separator=",">(#{org.orgId},#{org.paramInfo, typeHandler=com.xxx.xx.xxx.handle.JsonTypeHandler})</foreach></insert><resultMap id="orgResult" type="com.xxx.xxx.xxx.Org"><result property="orgId" column="orgid"/><result property="paramInfo" column="paraminfo" javaType="com.alibaba.fastjson.JSONObject" typeHandler="com.ins.iot.sync.server.handle.JsonTypeHandler"/></resultMap><select id="srg" resultMap="orgResult">selectorgid,paraminfofrom org</select>