查询所有一级部门和二级部门列表

ServiceImpl层：

@Override
    public List selectList(DeptDictDto exp) {
        log.info("【DeptDictService-selectList】，exp【" + JSON.toJSONString(exp) + "】");

        //查询设置
        QueryWrapper queryWrapper = new QueryWrapper<>();
        //添加查询列（默认查全字段）
        //queryWrapper.select("");

        //添加查询条件
        if(exp != null){
            //等于
            if(exp.getDeptId() != null){
                queryWrapper.eq("dept_id", exp.getDeptId());
            }
            if(exp.getDeptName() != null){
                queryWrapper.eq("dept_name", exp.getDeptName());
            }
            if(exp.getParentId() != null){
                queryWrapper.eq("parent_id", exp.getParentId());
            }
            if(exp.getDeleteFlag() != null){
                queryWrapper.eq("delete_flag", exp.getDeleteFlag());
            }
            if(exp.getUpdateUser() != null){
                queryWrapper.eq("update_user", exp.getUpdateUser());
            }
            if(exp.getUpdateDate() != null){
                queryWrapper.eq("update_date", exp.getUpdateDate());
            }

        //发起查询
        List pos = mapper.selectList(queryWrapper);

        //返回
        List dtos = null;
        if(!CollectionUtils.isEmpty(pos)){
            dtos = new ArrayList<>();
            for(DeptDict po: pos){
                DeptDictDto dto = new DeptDictDto();
                BeanUtils.copyProperties(po, dto);
                dtos.add(dto);
            }
        }
        return dtos;
    }

二级部门返回对象：SecondDeptVo.java

@Data
public class SecondDeptVo implements Serializable {
    private static final long serialVersionUID=1L;
    
    private String deptId;
    private String deptName;
}

出参：QueryAllDeptsResp.java

@Data
public class QueryAllDeptsResp implements Serializable {
    private static final long serialVersionUID=1L;

    private String deptId;
    private String deptName;
    private List secondDepts;
}

查询所有部门接口实现：

@PostMapping(value = "/queryAllDepts")
public ResultJson queryAllDepts() {
    ResultJson resultJson = new ResultJson();
    long time = System.currentTimeMillis();
    log.info("【查询所有部门】开始");

    //1.业务逻辑处理
    try {
        List respList = new ArrayList<>();
        //1.1查询
        DeptDictDto deptDictDto = new DeptDictDto();
        deptDictDto.setParentId("abc");//parentId为abc的均为一级部门
        //查询一级部门集合
        List deptDictDtos = deptDictService.selectList(deptDictDto);
        if (!CollectionUtils.isEmpty(deptDictDtos)) {
            log.info("返回所有一级部门条数【" + deptDictDtos.size() + "】");
            for (DeptDictDto dto : deptDictDtos) {
                List secondDepts = new ArrayList<>();
                QueryAllDeptsResp queryAllDeptsResp = new QueryAllDeptsResp();

                DeptDictDto exp = new DeptDictDto();
                exp.setParentId(dto.getDeptId());
                log.info("根据一级部门id查询所有一级部门入参parentId【" + dto.getDeptId() + "】");
                //查询二级部门集合
                List list = deptDictService.selectList(exp);
                if (!CollectionUtils.isEmpty(list)) {
                    log.info("根据一级部门id返回二级部门条数【" + list.size() + "】");
                    for (DeptDictDto dictDto : list) {
                        SecondDeptVo secondDeptVo = new SecondDeptVo();
                        secondDeptVo.setDeptId(dictDto.getDeptId());//二级部门id
                        secondDeptVo.setDeptName(dictDto.getDeptName());//二级部门name
                        secondDepts.add(secondDeptVo);
                    }
                }

                queryAllDeptsResp.setDeptId(dto.getDeptId());//一级部门id
                queryAllDeptsResp.setDeptName(deptDictApiService.getDeptNameById(dto.getDeptId()));//一级部门name
                queryAllDeptsResp.setSecondDepts(secondDepts);
                respList.add(queryAllDeptsResp);

                log.info("查询所有部门返回结果为：【" + JSON.toJSONString(respList) + "】");

            }
            resultJson = new ResultJson().success(respList);
        }
    } catch (
            Exception e) {
        log.error("【查询所有部门】出错，错误详情【" + e.getMessage() + "】", e);
        return new ResultJson(ResultEnum.SERVICE_ERR);
    }

    //1.2 返回
    log.info("【查询所有部门】结束，耗时【" + (System.currentTimeMillis() - time) + "】");
    return resultJson;
}

接口结果展示：

{
    "code": "200",
    "msg": "请求成功",
    "data": [
        {
            "deptId": "106600",
            "deptName": "专业中心",
            "secondDepts": [
                {
                    "deptId": "500_000191",
                    "deptName": "专业中心"
                }
            ]
        },
        {
            "deptId": "217568",
            "deptName": "市场部",
            "secondDepts": [
                {
                    "deptId": "500_000197",
                    "deptName": "市场中心"
                }
            ]
        },
        {
            "deptId": "98036",
            "deptName": "总裁办",
            "secondDepts": [
                {
                    "deptId": "500_000008",
                    "deptName": "决策部"
                },
                {
                    "deptId": "500_000139",
                    "deptName": "战略投资部"
                },
                {
                    "deptId": "500_000194",
                    "deptName": "科技项目"
                }
            ]
        },
        {
            "deptId": "98037",
            "deptName": "产品中心",
            "secondDepts": [
                {
                    "deptId": "500_000052",
                    "deptName": "产品部"
                }
            ]
        },
        {
            "deptId": "98038",
            "deptName": "技术中心",
            "secondDepts": [
                {
                    "deptId": "500_000012",
                    "deptName": "研发中心"
                }
            ]
        },
        {
            "deptId": "98040",
            "deptName": "财务部",
            "secondDepts": [
                {
                    "deptId": "500_000024",
                    "deptName": "财务"
                }
            ]
        },
        {
            "deptId": "98041",
            "deptName": "人力资源部",
            "secondDepts": [
                {
                    "deptId": "500_000028",
                    "deptName": "组织发展&人力资源部"
                }
            ]
        },
        {
            "deptId": "98043",
            "deptName": "公共事务部",
            "secondDepts": [
                {
                    "deptId": "500_000187",
                    "deptName": "创新项目部"
                },
                {
                    "deptId": "500_000188",
                    "deptName": "老项目部"
                }
            ]
        }
    ]
}