MyBatis Plus 将查询结果封装到指定实体的方法步骤_JAVA教程

思路

自定义方法，使用Wrapper，自定义映射结果集

Mapper接口

				?

									package com.mozq.boot.mpsand01.dao;

									import com.baomidou.mybatisplus.core.conditions.Wrapper;

									import com.baomidou.mybatisplus.core.mapper.BaseMapper;

									import com.baomidou.mybatisplus.core.toolkit.Constants;

									import com.mozq.boot.mpsand01.pojo.OrderInfo;

									import com.mozq.boot.mpsand01.vo.OrderVO;

									import org.apache.ibatis.annotations.*;

									import java.util.List;

									@Mapper

									public interface OrderInfoDao extends BaseMapper<OrderInfo> {

									  @Select("select * from order_info ${ew.customSqlSegment}")

									  /* 只指定2个，其他列能自动匹配的，也会被映射。

									  @Results({

									      @Result(id = true, column = "ORDER_ID", property = "orderId", jdbcType = JdbcType.VARCHAR),

									      @Result(column = "USER_ID", property = "userId", jdbcType = JdbcType.INTEGER)

									  })

									  */

									  List<OrderVO> findByCondition(@Param(Constants.WRAPPER)Wrapper wrapper);

									  List<OrderVO> selectOrderVOList(@Param(Constants.WRAPPER)Wrapper wrapper);

									}

Mapper.xml

				?

									<?xml version="1.0" encoding="UTF-8" ?>

									<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"

									    "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

									<mapper namespace="com.mozq.boot.mpsand01.dao.OrderInfoDao">

									  <resultMap id="BaseResultMapVO" type="com.mozq.boot.mpsand01.vo.OrderVO">

									    <id column="ORDER_ID" property="orderId" jdbcType="VARCHAR" />

									    <result column="USER_ID" property="userId" jdbcType="INTEGER" />

									    <result column="COMPANY_ID" property="companyId" jdbcType="INTEGER" />

									    <result column="CUSTOMER_ID" property="customerId" jdbcType="INTEGER" />

									    <result column="CUSTOMER_NAME" property="customerName" jdbcType="VARCHAR" />

									    <result column="MOBILE_PHONE" property="mobilePhone" jdbcType="VARCHAR" />

									    <result column="ACCOUNT_ID" property="accountId" jdbcType="VARCHAR" />

									    <result column="PRODUCT_ID" property="productId" jdbcType="INTEGER" />

									    <result column="PRODUCT_NAME" property="productName" jdbcType="VARCHAR" />

									    <result column="ORDER_TYPE" property="orderType" jdbcType="INTEGER" />

									    <result column="QUANTITY" property="quantity" jdbcType="DECIMAL" />

									    <result column="LICENSE_PLATE_NUMBER" property="licensePlateNumber" jdbcType="VARCHAR" />

									    <result column="PRICE" property="price" jdbcType="DECIMAL" />

									    <result column="TOTAL_MONEY" property="totalMoney" jdbcType="DECIMAL" />

									    <result column="PAY_QUANTITY" property="payQuantity" jdbcType="DECIMAL" />

									    <result column="PAY_MONEY" property="payMoney" jdbcType="DECIMAL" />

									    <result column="THE_WEIGHT" property="theWeight" jdbcType="INTEGER" />

									    <result column="DELIVERY_ADDRESS" property="deliveryAddress" jdbcType="VARCHAR" />

									    <result column="RECEIVE_ADDRESS" property="receiveAddress" jdbcType="VARCHAR" />

									    <result column="ORDER_STATUS" property="orderStatus" jdbcType="INTEGER" />

									    <result column="REMARK" property="remark" jdbcType="VARCHAR" />

									    <result column="PICKUP_TIME" property="pickupTime" jdbcType="TIMESTAMP" />

									    <result column="CREATE_TIME" property="createTime" jdbcType="TIMESTAMP" />

									    <result column="UPDATE_TIME" property="updateTime" jdbcType="TIMESTAMP" />

									  </resultMap>

									  <sql id="Base_Column_List">

									    ORDER_ID,

									    USER_ID,

									    COMPANY_ID,

									    CUSTOMER_ID,

									    CUSTOMER_NAME,

									    MOBILE_PHONE,

									    ACCOUNT_ID,

									    PRODUCT_ID,

									    PRODUCT_NAME,

									    ORDER_TYPE,

									    QUANTITY,

									    LICENSE_PLATE_NUMBER,

									    PRICE,

									    TOTAL_MONEY,

									    PAY_QUANTITY,

									    PAY_MONEY,

									    THE_WEIGHT,

									    DELIVERY_ADDRESS,

									    RECEIVE_ADDRESS,

									    ORDER_STATUS,

									    REMARK,

									    PICKUP_TIME,

									    CREATE_TIME,

									    UPDATE_TIME

									  </sql>

									  <select id="selectOrderVOList" resultMap="BaseResultMapVO">

									    select <include refid="Base_Column_List"></include>

									    from order_info

									    ${ew.customSqlSegment}

									  </select>

									</mapper>

测试类

				?

									@Test

									public void selectOrderVOList(){

									  List<OrderVO> orderVOList = orderInfoDao.selectOrderVOList(

									    Wrappers.<OrderInfo>lambdaQuery()

									    .eq(OrderInfo::getUserId, 123456)

									    .eq(OrderInfo::getCompanyId, 1)

									  );

									  System.out.println(orderVOList.size());

									  List<OrderVO> byCondition = orderInfoDao.findByCondition(

									    Wrappers.<OrderInfo>lambdaQuery()

									    .eq(OrderInfo::getUserId, 123456)

									    .eq(OrderInfo::getCompanyId, 1)

									  );

									  System.out.println(byCondition.size());

									  List<OrderInfo> orderInfoList = orderInfoDao.selectList(

									    Wrappers.<OrderInfo>lambdaQuery()

									    .eq(OrderInfo::getUserId, 123456)

									    .eq(OrderInfo::getCompanyId, 1)

									  );

									  System.out.println(orderInfoList.size());

									}