递归查询树

递归查部门树

1.数据

2.实体

private String id;
private String name;
private String pid;
private List<Dept> child ;

3.sql

<select id="selectTrees" resultMap="BaseResultMap">
  select * from dept where pid = #{pid,jdbcType=VARCHAR}
</select>

4.mapper

List<Dept>selectTrees(String pid);

5.controller

@Test
void contextLoads() {
    List<Dept> deptList = getDeptList("0");
    System.out.println(deptList);
}

List<Dept> getDeptList(String pid) {
    List<Dept> Depts = deptMapper.selectTrees(pid);
    if (Depts.size() > 0) {
        for (int i = 0; i < Depts.size(); i++) {
            List<Dept> dtos = getDeptList(Depts.get(i).getId());
            Depts.get(i).setChild(dtos);
        }
    }
    return Depts;
}