集合根据属性分组思路

先创建结果结构，然后直接getOrDefault，最后put。

    private Map<String, Map<String, ResourceBean>> covertResourceToMap(List<ResourceDto> resourceList) {
        // hotlineId,serviceCode
        Map<String, Map<String, ResourceBean>> result = new HashMap<>();
        for (ResourceDto resourceDto : resourceList) {
            Map<String, ResourceBean> serviceCodeGroup = result.getOrDefault(resourceDto.getHotlineId(), new HashMap<>());
            // 取出当前serviceCode的ResourceBean
            ResourceBean resourceBean = serviceCodeGroup.getOrDefault(resourceDto.getServiceCode(), new ResourceBean());
            // 封装前根据type区分菜单数据和权限点数据
            if (ResourceTypeEnum.MENU.getType().equals(resourceDto.getType())) {
                // 如果是菜单数据，则封装
                addMenuList(resourceBean, resourceDto);
            } else if (ResourceTypeEnum.PERMISSION.getType().equals(resourceDto.getType())) {
                // 如果是资源点数据，则封装
                addPermissionList(resourceBean, resourceDto);
            } else {
                log.warn("未知资源类型，resourceType:{}", resourceDto.getType());
            }
            // 处理完毕后封装进map结构
            serviceCodeGroup.put(resourceDto.getServiceCode(), resourceBean);
            result.put(resourceDto.getHotlineId(), serviceCodeGroup);
        }
        return result;
    }
        private void addMenuList(ResourceBean resourceBean, ResourceDto resourceDto) {
        List<MenuVO> menuList = Optional.ofNullable(resourceBean.getMenuList()).orElse(new ArrayList<>());
        MenuVO menuVO = new MenuVO();
        BeanUtils.copyProperties(resourceDto, menuVO);
        menuList.add(menuVO);
        resourceBean.setMenuList(menuList);
    }
    private void addPermissionList(ResourceBean resourceBean, ResourceDto resourceDto) {
        List<PermissionVO> permissionList = Optional.ofNullable(resourceBean.getPermissionList()).orElse(new ArrayList<>());
        PermissionVO permissionVO = new PermissionVO();
        BeanUtils.copyProperties(resourceDto, permissionVO);
        permissionList.add(permissionVO);
        resourceBean.setPermissionList(permissionList);
    }

相同结构的树与树之间进行信息填充转换递归方式

    private static void buildMenuTreeByMenuIdVo(MenuIdVO menuIdVO, Map<String, String> resourceCache, MenuVO result) {
        ResourceEntity resourceEntity = JSONObject.parseObject(resourceCache.get(String.valueOf(menuIdVO.getId())),
            ResourceEntity.class);
        BeanUtils.copyProperties(resourceEntity, result);
        if (CollectionUtils.isEmpty(menuIdVO.getChildrenIds())) {
            return;
        }
        for (MenuIdVO m : menuIdVO.getChildrenIds()) {
            MenuVO menuVO = new MenuVO();
            buildMenuTreeByMenuIdVo(m, resourceCache, menuVO);
            Optional.ofNullable(result.getChildren()).orElse(new ArrayList<>()).add(menuVO);
        }
    }