【作者】 李燏；

【导师】 陈定方； 钱开元；

【作者基本信息】 武汉理工大学 ， 机械设计与理论， 2002， 硕士

【摘要】 20世纪90年代出现了分布式对象技术，为网络软件的开发提供了强有力的解决方案。分布式计算技术是指在网络计算平台上开发、部署、管理和维护以资源共享和协同工作为主要应用目标的分布式应用系统。目前，分布式对象技术已经成为建立服务应用框架和软件构件的核心技术，在开发大型分布式应用系统中表现出强大的生命力。 随着Internet技术的发展与普及，基于Web的Browser／Server应用系统孕育而生并迅猛发展。目前的Web技术虽然拥有不少独特的优点，但无法胜任大规模的企业计算。其主要问题在于系统需要HTTP和Web服务器作为中介，来协调应用服务器和客户机对象之间的通信，这必然在Web服务器处形成“瓶颈”，造成响应速度减慢。而分布式对象技术允许在不同机器上的对象相互传递消息。因此，将Web技术与分布式技术两者相互结合将可以解决上述问题，使客户端对象越过Web服务器直接调用应用服务器对象，从而提高系统的性能。Web技术、分布式对象技术的有机结合将是Web系统今后的一大发展趋势。 本论文进行基于分布式对象的Web系统的研究与应用。本文的主要研究工作如下： 1、对分布式对象技术进行了综述，深入研究了分布式对象技术的三种主流技术：COM／DCOM技术、J2EE／EJB技术和COBRA技术，并对这三种技术进行了分析、比较。 2、对Web应用体系结构进行了分析，并针对目前的Web体系结构的弊端，结合分布式对象技术，提出并分析了基于分布式对象的Web应用体系结构。 3、对CSCW技术进行了综述，分析了CSCW的基本特征、典型结构和一些关键技术；作为CSCW技术的一个典型应用，基于J2EE架构，建立了一个基于分布式对象技术的Web应用系统——Web会议系统。分析了Web会议系统的体系结构、功能、原理，介绍了系统中采用的关键技术。建立的Web会议系统采用了JMS、JNDI、JDBC、EJB等技术，通过JMS的订阅／发布技术实现多个会议成员的消息的实时异步传输。更多还原

【Abstract】 Distributed object technology that occurred in 90’s provides a strongly solution for the development of network software. Distributed computing technology is to develop, deploy, manage and maintain distributed application system whose main application goal is to implement resource share and cooperative work on the network computing platform. Now, distributed object technology has become the core technology of building service application framework and software component. It shows great life-force in developing large distributed application systems.With the development and popularity of Internet, Web based Browser/Server application system came into being and is swiftly developing. Although current Web technology is of some unique merits, it still can’t complete large-scale enterprise computing. The main problem is that system requires HTTP and Web Server as agency to correspond the communication of application server and client. This must cause the flux bottleneck that will slower the response speed on Web Server. Meanwhile distributed object technology allows mutual information communications among objects on different machines. Hence the combination of Web technology and distributed object technology can solve above problem. It will make client call application object cross the Web Server and improve the performance of the system. The integration of Web technology and distributed object technology is the development trend of Web system.This paper focuses on Web Research and Application on Web system based on distributed object. The main contributions of this thesis is described as following:1. Introduces distributed object technology, deeply studies the 3 mainstream technologies: COM/DCOM technology, J2EE/EJB technology and COBRA technology, then analyzes and compares the 3 technologies.2. Analyzes the Web application system architecture, according to the disadvantage of current Web system architecture,.proposes and analyzes Web application system architecture based on distributed object technology integrating distributed object technology.3. Introduces the CSCW technology, analyzes the basic features, typical structure and some key technologies of CSCW. Constructs a Web applicationsystem------Web conference system which is a representative application ofCSCW technology based on distributed object technology------J2EE architecture.Analyzes the system architecture, the function and the principle of Web conference system, introduces the key technologies adopted in this system. This system uses IMS, JNDI, JDBC, EJB etc. technologies, implements real message asynchronism transfer of many conference members via Subscribe/Publish of IMS technology.更多还原