本代码利用java rmi实现了一个基本的在线共享画图板功能。基本功能包括，用户成员管理，基本画图功能（各种线条、颜色、背景、基本图形选择、文字输入，清空），复制粘贴，保存、载入文件-This code is used to achieve a basic java rmi-online sharing drawing board. Basic features include, user membership management, and basic drawing functions (a