2. 程式人生 > 程式設計 >myBatis實現三級巢狀複雜物件的賦值問題

myBatis實現三級巢狀複雜物件的賦值問題

阿新 • • 發佈：2020-11-13

平常我們工作中基本最多兩級巢狀，但是有時候難免會遇到三級巢狀的業務場景，筆者最近就碰到了，使用一般的巢狀發現賦值為空，這可難倒了菜逼的我，後來在stackoverflow的幫助下終於搜到瞭解決辦法，完美解決了問題 ，總結一下，方便有需要的同學，下面直接上栗子：

首先上實體類：三級巢狀如下 （電站 -----> 電樁 ---->電槍）

電站實體類 (實體為JPA寫法，不影響mybatis的使用)

package com.weima.cecapp.entities;

import lombok.Data;
import lombok.NoArgsConstructor;
import org.hibernate.annotations.BatchSize;
import org.hibernate.annotations.GenericGenerator;

import javax.persistence.*;
import java.util.Collections;
import java.util.List;
import java.util.Set;
@NoArgsConstructor
@Data
@Entity
@Table(name = "station_info")
public class StationInfo {
  /**
   * Auto-generated primary key.
   */
  @Id
  @GeneratedValue(generator = "uuid")
  @GenericGenerator(name = "uuid",strategy = "org.hibernate.id.UUIDGenerator")
  @Column(unique = true,nullable = false,updatable = false)
  private String id;

  @Column(name = "station_id")
  private String stationId;

  @Column(name = "operator_id")
  private String operatorId;

  @Column(name = "equipment_owner_id")
  private String equipmentOwnerId;

  @Column
  private String stationName;

  @Column
  private String countryCode;

  @Column
  private String areaCode;

  @Column
  private String address;

  @Column
  private String stationTel;

  @Column
  private String serviceTel;

  @Column
  private Integer stationType;

  @Column
  private Integer stationStatus;

  @Column
  private Integer parkNums;

  @Column
  private Double stationLng;

  @Column
  private Double stationLat;

  @Column
  private String siteGuide;

  @Column
  private Integer construction;

  @OneToMany(fetch = FetchType.LAZY,cascade = {CascadeType.ALL},orphanRemoval = true,mappedBy = "ownerStationInfo")
  private List<StationPicture> pictures;

  @Column
  private String matchCars;

  @Column
  private String parkInfo;

  @Column
  private String busineHours;

  @Column(name = "busine_hours_in_milliseconds")
  private Long busineHoursInMilliseconds;

  @Column
  private String electricityFee;

  @Column
  private String serviceFee;

  @Column
  private String parkFee;

  @Column
  private String payment;

  @Column
  private Integer supportOrder;

  @Column
  private String remark;

  @OneToMany(fetch = FetchType.LAZY,mappedBy = "ownerStationInfo")
  @BatchSize(size = 20)
  private List<EquipmentInfo> equipmentInfos;

}

電站圖片實體

package com.weima.cecapp.entities;

import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.ToString;
import org.hibernate.annotations.GenericGenerator;

import javax.persistence.*;

@Data
@Entity
@EqualsAndHashCode(of = {"url"})
@ToString(exclude = {"ownerStationInfo"})
@Table(name = "station_picture")
public class StationPicture {
  /**
   * Auto-generated primary key.
   */
  @Id
  @GeneratedValue(generator = "uuid")
  @GenericGenerator(name = "uuid",insertable = true,updatable = false)
  private String id;

  @ManyToOne(fetch = FetchType.EAGER,optional = false)
  @JoinColumn(nullable = false,updatable = false)
  private StationInfo ownerStationInfo;

  @Column
  private String url;
}

電樁實體類

package com.weima.cecapp.entities;

import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.ToString;
import org.hibernate.annotations.BatchSize;
import org.hibernate.annotations.GenericGenerator;

import javax.persistence.*;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Collections;
import java.util.List;

@Data
@Entity
@EqualsAndHashCode(of = {"equipmentId"})
@ToString(exclude = {"ownerStationInfo"})
@Table(name = "equipment_info")
public class EquipmentInfo {
  /**
   * Auto-generated primary key.
   */
  @Id
  @GeneratedValue(generator = "uuid")
  @GenericGenerator(name = "uuid",updatable = false)
  private String id;

  @Column(name = "equipment_id")
  private String equipmentId;

  @ManyToOne(fetch = FetchType.EAGER,updatable = false)
  private StationInfo ownerStationInfo;

  @Column(name = "manufacturer_id")
  private String manufacturerId;

  @Column
  private String manufacturerName;

  @Column
  private String equipmentModel;

  @Column
  private String productionDate;

  public String getProductionDate() {
    String format = null;
    if (this.productionDate != null) {
      SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
      try {
        format = sdf.format(sdf.parse(this.productionDate));
      } catch (ParseException e) {
        e.printStackTrace();
      }
      return format;
    }
    return format;
  }

  @Column
  private String equipmentType;

  @OneToMany(fetch = FetchType.LAZY,mappedBy = "ownerEquipmentInfo",cascade = {CascadeType.PERSIST})
  @BatchSize(size = 20)
  private List<ConnectorInfo> connectorInfos;

  @Column
  private Double equipmentLng;

  @Column
  private Double equipmentLat;

  @Column
  private Double power;

  @Column
  private String equipmentName;

  @Column(name = "equipment_no")
  //cpo's custom equipmentId mostly for Evstation
  private String equipmentNo;
}

電槍實體類

package com.weima.cecapp.entities;

import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.ToString;
import org.hibernate.annotations.GenericGenerator;

import javax.persistence.*;

@Data
@Entity
@EqualsAndHashCode(of = {"connectorId"})
@ToString(exclude = {"ownerEquipmentInfo"})
@Table(name = "connector_info")
public class ConnectorInfo {
  /**
   * Auto-generated primary key.
   */
  @Id
  @GeneratedValue(generator = "uuid")
  @GenericGenerator(name = "uuid",updatable = false)
  private EquipmentInfo ownerEquipmentInfo;

  @Column(name = "connector_id")
  private String connectorId;

  @Column
  private String connectorName;

  @Column
  private Integer connectorType;

  @Column
  private Integer voltageUpperLimits;

  @Column
  private Integer voltageLowerLimits;

  @Column
  private Integer current;

  @Column
  private Double power;

  @Column
  private String parkNo;

  @Column
  private Integer nationalStandard;

  @Column(name = "connector_no")
  //cpo's custom connectorId mostly for Evstation
  private String connectorNo;
}

mapper 檔案的resultMap對映及Sql語句的書寫，要特別注意對映關係

<?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.hubject.cecapp.mapper.StationInfoAnyueMapper">

  <resultMap id="templateListResp" type="com.hubject.cecapp.entities.EquipmentInfo">
    <!-- 充電樁資訊-->
    <id column  ="id          " property="id"/>
    <result column="equipment_id     " property="equipmentId"/>
    <result column="equipment_lat     " property="manufacturerName"/>
    <result column="equipment_lng     " property="equipmentModel"/>
    <result column="equipment_model    " property="productionDate"/>
    <result column="equipment_name    " property="manufacturerId"/>
    <result column="equipment_type    " property="equipmentType"/>
    <result column="manufacturer_id    " property="equipmentLng"/>
    <result column="manufacturer_name   " property="equipmentLat"/>
    <result column="power         " property="power"/>
    <result column="production_date    " property="equipmentName"/>
    <result column="owner_station_info_id " property="equipmentNo"/>
      <!-- 充電槍 資訊列表 -->
    <collection property="connectorInfos" columnPrefix="f_" ofType="com.hubject.cecapp.entities.ConnectorInfo">
      <id column="id" property="id"/>
      <result column="connector_id" property="connectorId"/>
      <result column="connector_name" property="connectorName"/>
      <result column="connector_type" property="connectorType"/>
      <result column="voltage_upper_limits" property="voltageUpperLimits"/>
      <result column="voltage_lower_limits" property="voltageLowerLimits"/>
      <result column="current" property="current"/>
      <result column="power" property="power"/>
      <result column="park_no" property="parkNo"/>
      <result column="national_standard" property="nationalStandard"/>
      <result column="connector_no" property="connectorNo"/>
    </collection>
  </resultMap>

  <!-- 通用查詢對映結果 -->
  <resultMap id="Base3ResultMap" type="com.hubject.cecapp.entities.StationInfo">
    <result column="id" property="id"/>
    <result column="address" property="address"/>
    <result column="area_code" property="areaCode"/>
    <result column="busine_hours" property="busineHours"/>
    <result column="construction" property="construction"/>
    <result column="country_code" property="countryCode"/>
    <result column="electricity_fee" property="electricityFee"/>
    <result column="equipment_owner_id" property="equipmentOwnerId"/>
    <result column="station_id" property="stationId"/>
    <result column="operator_id" property="operatorId"/>
    <result column="station_name" property="stationName"/>
    <result column="station_tel" property="stationTel"/>
    <result column="service_tel" property="serviceTel"/>
    <result column="station_type" property="stationType"/>
    <result column="station_status" property="stationStatus"/>
    <result column="park_nums" property="parkNums"/>
    <result column="station_lng" property="stationLng"/>
    <result column="station_lat" property="stationLat"/>
    <result column="site_guide" property="siteGuide"/>
    <result column="match_cars" property="matchCars"/>
    <result column="park_info" property="parkInfo"/>
    <result column="busine_hoursIn_milliseconds" property="busineHoursInMilliseconds"/>
    <result column="service_fee" property="serviceFee"/>
    <result column="park_fee" property="parkFee"/>
    <result column="payment" property="payment"/>
    <result column="support_order" property="supportOrder"/>
    <result column="remark" property="remark"/>
    <result column="templateListResp" property="remark"/>
    <collection property="equipmentInfos" columnPrefix="t_" resultMap="templateListResp"/>
  </resultMap>


-- 要特別注意的是 t_f_ 的字首，這個關乎到對映不對映上的根本。
<select id="queryAreaForAnyoCharging" resultMap="Base3ResultMap">
    select
       a.id                   as    id,a.station_id               as    station_id,a.operator_id              as    operator_id,a.equipment_owner_id           as    equipment_owner_id,a.station_name              as    station_name,a.country_code              as    country_code,a.area_code               as    area_code,a.address                as    address,a.station_tel              as    station_tel,a.service_tel              as    service_tel,a.station_type              as    station_type,a.station_status             as    station_status,a.park_nums               as    park_nums,a.station_lng              as    station_lng,a.station_lat              as    station_lat,a.site_guide               as    site_guide,a. construction             as    construction,a.match_cars               as    match_cars,a.park_info               as    park_info,a.busine_hours              as    busine_hours,a.busine_hours_in_milliseconds      as    busine_hours_in_milliseconds,a. electricity_fee            as    electricity_fee,a. service_fee              as    service_fee,a. park_fee               as    park_fee,a. payment                as    payment,a. support_order             as    support_order,a.remark                 as    remark,e.id                   as    t_id,e.equipment_id              as    t_equipment_id,e.equipment_lat             as    t_equipment_lat,e.equipment_lng             as    t_equipment_lng,e.equipment_model            as    t_equipment_model,e.equipment_name             as    t_equipment_name,e.equipment_type             as    t_equipment_type,e.manufacturer_id            as    t_manufacturer_id,e.manufacturer_name           as    t_manufacturer_name,e.power                 as    t_power,e.production_date            as    t_production_date,e.owner_station_info_id         as    t_owner_station_info_id,e.equipment_no              as    t_equipment_no,c.id                   as    t_f_id,c.power                 as    t_f_power,c.current                as    t_f_current,c.park_no                as    t_f_park_no,c.connector_id              as    t_f_connector_id,c.connector_name             as    t_f_connector_name,c.connector_type             as    t_f_connector_type,c.connector_no              as    t_f_connector_no,c.national_standard           as    t_f_national_standard,c.voltage_lower_limits          as    t_f_voltage_lower_limits,c.voltage_upper_limits          as    t_f_voltage_upper_limits,c.owner_equipment_info_id        as    t_f_owner_equipment_info_id

       from station_info a join equipment_info e on a.id = e.owner_station_info_id

         join connector_info c on e.id = c.owner_equipment_info_id

         where a.operator_id='MA59J8YL8'
  </select>
  
  </mapper>

希望為遇到同樣需求的同學提供到幫助。

到此這篇關於myBatis實現三級巢狀複雜物件的賦值問題的文章就介紹到這了,更多相關myBatis三級巢狀複雜物件的賦值內容請搜尋我們以前的文章或繼續瀏覽下面的相關文章希望大家以後多多支援我們！

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