说明：  基于Java-RMI（远程方法调用）实现一个小型的分布式系统，基本功能如下： 1) 提供并显示当前时间的服务器端。 2) 获取并用模拟和数字两种时钟按指定时间间隔显示时间的客户端。
(Based on Java-RMI (remote method invocation) to achieve a small-scale distributed systems, the basic functions are as follows: 1) to provide and display the current time of the server-side. 2) access to and use of two types of analog and digital clock display according to a specified time interval of time the client.)