A java-rmi chat-room,instant messaging is one particular application in a broader class of applications known as presence-based applications. Presence-based applications are inherently distributed applications that build on the notion of a user’s

本系统是为方便企业内部进行简单办公，方便员工进行交流为基础，为企业提供较为完善的即时沟通和实时协作的解决方案。(This system uses Java language and eclipse as the basic development environment, using the software refactoring development approach, the original system design is optimized, by using the princi