递归--java递归返回路由

表结构

目录级的parent_id为0

代码

 @Override
    public List<SysMenu> selectRouterTreeByUserId(Long userId)
    {

        List<SysMenu> menus = null;
        menus = SysRouterMapper.selectRouterTreeByUserId(userId);
        return getChildPerms(menus, 0);
    }

    public List<SysMenu> getChildPerms(List<SysMenu> list, int parentId)
    {
        for(Iterator<SysMenu> iterator = list.iterator(); iterator.hasNext();){
            SysMenu t = (SysMenu) iterator.next();
            if(t.getParentId() == parentId){
//              通过递归获取父节点的所有子节点
                recursionFn(list, t);
            }
        }
        return list;
    }

    public void recursionFn(List<SysMenu> list, SysMenu t)
    {
//        获取子节点
        List<SysMenu> childList = getChildList(list, t);
        t.setChildren(childList);
//        判断子节点是否还有子节点，有则继续递归
        for(Iterator<SysMenu> iterator = childList.iterator(); iterator.hasNext();){
            SysMenu tChild = (SysMenu) iterator.next();
            if(hasChild(list, tChild)){
                recursionFn(list, tChild);
            }
        }
    }

    private boolean hasChild(List<SysMenu> list, SysMenu tChild) {
        return getChildList(list, tChild).size() > 0;
    }

    public List<SysMenu> getChildList (List<SysMenu> list, SysMenu t){
        List<SysMenu> childList = new ArrayList<SysMenu>();
        for(Iterator<SysMenu> iterator = list.iterator(); iterator.hasNext();){
            SysMenu node = (SysMenu) iterator.next();

            if(node.getParentId().longValue() == t.getMenuId().longValue()){
                childList.add(node);
            }
        }
        return childList;
    }