1.地区树形结构

/**
 * 地区树形结构
 * @author xzx
 * @date 2021/12/21 16:47
 */
public class DistrictVo {

    private String code;
    private String parentCode;
    private String name;
    private List<DistrictVo> chridrenList;


    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getParentCode() {
        return parentCode;
    }

    public void setParentCode(String parentCode) {
        this.parentCode = parentCode;
    }

    public List<DistrictVo> getChridrenList() {
        return chridrenList;
    }

    public void setChridrenList(ArrayList<DistrictVo> chridrenList) {
        this.chridrenList = chridrenList;
    }
}

2.查询地区集合

  public List<DistrictVo> treeDistrictByOrgCode(String orgCode) {
        List<DistrictVo> districtVos = sysTDistrictMapper.treeDistrictByOrgCode(orgCode);
        if (!CollectionUtils.isEmpty(districtVos)){
            if (!Objects.equals("00",districtVos.get(0).getParentCode())){
                districtVos.get(0).setParentCode("00");
            }
        }
        return this.buildTreeDistrict(districtVos);
    }

3.sql

select code,parent_code as parentCode, name from sys_t_district where  code like concat(#{orgCode},'%') and  level in ("1","2","3","4")

4.构建树结构

private List<DistrictVo> buildTreeDistrict(List<DistrictVo> districtVos) {
        List<DistrictVo> trees = new ArrayList<DistrictVo>();
        for (DistrictVo treeNode : districtVos) {
            if ("00".equals(treeNode.getParentCode())) {
                trees.add(findChildren(treeNode,districtVos));
            }
        }
        return trees;
    }
    /**
     * 递归查找子节点
     * @param treeNodes
     * @return
     */
    public DistrictVo findChildren(DistrictVo treeNode,List<DistrictVo> treeNodes) {
        //treeNode.setChridrenList(new ArrayList<DistrictVo>());

        for (DistrictVo it : treeNodes) {
            if(treeNode.getCode().equals(it.getParentCode())) {
                if (treeNode.getChridrenList() == null) {
                    treeNode.setChridrenList(new ArrayList<DistrictVo>());
                }
                treeNode.getChridrenList().add(findChildren(it,treeNodes));
            }
        }
        return treeNode;
    }