MyBatis Plus 将查询结果封装到指定实体的方法步骤

时间:2020-09-25 魔有追求人气:0

本文着重讲解了MyBatis Plus 将查询结果封装到指定实体的方法步骤，文中通过代码实例讲解的非常细致，对大家的工作和学习具有一定的参考学习价值，需要的朋友们下面随着小编来一起学习学习吧

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());
}

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