Mybatis 递归查询树形菜单

雨点打透心脏的1/2处 2023-02-17 11:17 21阅读 0赞

### 文章目录 ###

*   *   *   *   *  1、数据库表结构
                 *  2、查询结果展示
                 *  3、实体类Department.java
                 *  4、DepartmentMapper.xml
                 *  5、DepartmentMapper.java

##### 1、数据库表结构 #####

![在这里插入图片描述][2020061317180452.png]

CREATE TABLE `department` (
      `id` int(11) NOT NULL AUTO_INCREMENT,
      `name` varchar(32) DEFAULT NULL COMMENT '部门名称',
      `parentId` int(11) DEFAULT NULL,
      PRIMARY KEY (`id`) USING BTREE
    ) ENGINE=InnoDB AUTO_INCREMENT=95 DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC COMMENT='部门表';

##### 2、查询结果展示 #####

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NodWFpODYyNA_size_16_color_FFFFFF_t_70]

##### 3、实体类Department.java #####

public class Department implements Serializable { 
        private Integer id;
        private String name;
        private Integer parentId;
        private List<Department> children = new ArrayList<>();
        //省略get\set

##### 4、DepartmentMapper.xml #####

<resultMap id="deptTree" type="com.chouxiaozi.vhr.model.Department">
          <id column="id" property="id" jdbcType="INTEGER" />
          <result column="name" property="name" jdbcType="VARCHAR" />
          <result column="parentId" property="parentId" jdbcType="INTEGER" />
        
        <collection property="children" column="id" select="getDeptTree" ofType="com.chouxiaozi.vhr.model.Department"></collection>
      </resultMap>
      
      <select id="getDeptTree" resultMap="deptTree">
        select * from department where parentId = #{ id}
      </select>

##### 5、DepartmentMapper.java #####

List<Department> getDeptTree(@Param("id") Integer parentId);

调用接口传入父id，即可递归查询子节点；常用于菜单或树形展示

[2020061317180452.png]: https://img-blog.csdnimg.cn/2020061317180452.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NodWFpODYyNA_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200613172511556.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NodWFpODYyNA==,size_16,color_FFFFFF,t_70