Spring boot 项目（三）—— mybatis-plus构建菜单树

controller

    @RequestMapping("menuTree")
    public Object menuTree(){
        return service.listSysMenuWithTree();
    }

service

public interface SysMenuService extends IService<SysMenu> 
   
    Object listSysMenuWithTree();

serviceImpl

public class SysMenuServiceImpl extends ServiceImpl<SysMenuMapper, SysMenu> implements SysMenuService 

    @Override
    public Object listSysMenuWithTree() {
        // 获取所有菜单
        List<SysMenu> sysMenuList = list(new LambdaQueryWrapper<SysMenu>()
                .eq(SysMenu::getMenuType, GlobalConstant.MENU_TYPE_ME)
        );
        // 一级菜单  =>  jdk8 流操作
        List<SysMenu> firstMenuList = sysMenuList.stream()
                // 过滤出一级菜单
                .filter(s -> s.getMenuParentId().equals(GlobalConstant.MENU_TOP))
                // 返回list集合形式
                .collect(Collectors.toList());
        // 遍历一级菜单 构造菜单树
        for (SysMenu sysMenu : firstMenuList) {
            getChildren(sysMenu, sysMenuList);
        }
        if (firstMenuList.size() != 0) {
            return ResultJson.ok("查询成功", firstMenuList);
        } else {
            return ResultJson.error("查询失败");
        }
    }

    /**
     * 获取子菜单
     */
    private SysMenu getChildren(SysMenu sysMenu, List<SysMenu> sysMenuList) {

        for (SysMenu menu : sysMenuList) {

            if (menu.getMenuParentId().equals(sysMenu.getId())) {

                sysMenu.getChildrenList().add(getChildren(menu, sysMenuList));
            }
        }
        return sysMenu;
    }

entity

    private Long id;
    //资源名称
    private String menuName;
    //权限
    private String menuPermission;
    //对应url
    private String menuPath;
    //父节点id
    private Long menuParentId;
    //菜单类型0菜单，1栏目类型
    private Integer menuType;
    //排序字段：值越小 顺序越靠前
    private Integer orderNum;
    //创建时间
    private LocalDateTime createTime;
    //最后更新时间
    private LocalDateTime updateTime;
    //子菜单集合
    @TableField(exist = false)
    private Set<SysMenu> childrenList=new HashSet<>();