mybatis-地区三表生成地区树

package com.dhht.manager.vo.area;

import lombok.Data;

import java.io.Serializable;
import java.util.List;

/**
 * @Author: sh
 * @Description: ProvinceVO
 * @Date: 19:33 2019/12/23
 */
@Data
public class ProvinceVO implements Serializable {
    private static final long serialVersionUID = 8581900297888963919L;
    private Long id;
    private String name;
    private String code;
    private Long regionLevel;
    private String regionName;
    private Long parentId;
    private List<CityVO> children;
}

package com.dhht.manager.vo.area;

import lombok.Data;

import java.io.Serializable;
import java.util.List;

/**
 * @Author: sh
 * @Description: CityVO
 * @Date: 19:33 2019/12/23
 */
@Data
public class CityVO implements Serializable {
    private static final long serialVersionUID = -4506315529106267971L;
    private Long id;
    private String name;
    private String code;
    private Long regionLevel;
    private String regionName;
    private Long parentId;
    private List<DistrictVO> children;
}

package com.dhht.manager.vo.area;

import lombok.Data;

import java.io.Serializable;
import java.util.List;

/**
 * @Author: sh
 * @Description: DistrictVO
 * @Date: 19:35 2019/12/23
 */
@Data
public class DistrictVO implements Serializable {
    private static final long serialVersionUID = 6682075711606147829L;

    private Long id;
    private String name;
    private String code;
    private Long regionLevel;
    private String regionName;
    private Long parentId;
    private List<Object> children;
}

package com.dhht.dao;

import com.dhht.manager.vo.area.DistrictVO;
import com.dhht.manager.vo.area.ProvinceVO;
import com.dhht.model.City;
import org.apache.ibatis.annotations.Param;

import java.util.List;

public interface CityMapper {

    List<ProvinceVO> treeProvinceQuery(@Param(value = "code")String code);

    List<City> treeCityQuery(@Param(value = "id")Long id);

    List<DistrictVO> treeDistrictQuery(@Param(value = "id")Long id);
}

<?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.dhht.dao.CityMapper">
  <!--province-->
  <resultMap id="provinceVoMap" type="com.dhht.manager.vo.area.ProvinceVO">
    <id column="id" jdbcType="BIGINT" property="id" />
    <result column="name" jdbcType="VARCHAR" property="name" />
    <result column="code" jdbcType="VARCHAR" property="code" />
    <result column="parentId" jdbcType="BIGINT" property="parentId" />
    <collection property="children" column="id" select="com.dhht.dao.CityMapper.treeCityQuery"></collection>
  </resultMap>
  <!--end province-->

  <!--city-->
  <resultMap id="cityVoMap" type="com.dhht.manager.vo.area.CityVO">
    <id column="id" jdbcType="BIGINT" property="id" />
    <result column="name" jdbcType="VARCHAR" property="name" />
    <result column="code" jdbcType="VARCHAR" property="code" />
    <result column="parentId" jdbcType="BIGINT" property="parentId" />
    <collection property="children" column="id" select="com.dhht.dao.CityMapper.treeDistrictQuery"></collection>
  </resultMap>
  <!--end city-->

  <!--district-->
  <resultMap id="districtVoMap" type="com.dhht.manager.vo.area.DistrictVO">
    <id column="id" jdbcType="BIGINT" property="id" />
    <result column="name" jdbcType="VARCHAR" property="name" />
    <result column="code" jdbcType="VARCHAR" property="code" />
    <result column="parentId" jdbcType="BIGINT" property="parentId" />
  </resultMap>
  <!--end district-->
  <resultMap id="BaseResultMap" type="com.dhht.model.City">
    <id column="id" jdbcType="BIGINT" property="id" />
    <result column="name" jdbcType="VARCHAR" property="name" />
    <result column="province_id" jdbcType="BIGINT" property="provinceId" />
    <result column="code" jdbcType="VARCHAR" property="code" />
  </resultMap>

  <select id="treeProvinceQuery" resultMap="provinceVoMap">
    select id,name,code,NULL AS parentId
    from lv_province
    WHERE CODE=#{code}
  </select>

  <select id="treeCityQuery" resultMap="cityVoMap">
    select id,name,code,#{id} AS parentId
    from lv_city
    WHERE province_id=#{id}
  </select>

  <select id="treeDistrictQuery" resultMap="districtVoMap">
    select id,name,code,#{id} AS parentId
    from lv_district
    WHERE city_id=#{id}
  </select>
</mapper>