摘要
本文着重讨论了基于简单对象访问协议SOAP的知识系统的应用程序集成模型。SOAP是WEB服务的核心协议,它为应用之间的无缝互联提供了一种简单通用的通信机制。Web服务的缺点是缺乏集中控制。知识系统框架是一种以具有集中控制和紧密耦合为特征的系统框架。该类型系统一般比较庞大,维护比较困难,而且目前大多数知识系统面临着不断出现的新技术的挑战。因此如何设计一种既能集成新型应用又能集成传统应用,且具有跨平台特性的应用程序集成模型,将是一件十分有意义的工作。
本文主要研究工作有三个方面:一是采用了动态Wrapper的机制来实现遗留系统的动态注册与互联。二是加入采用轻型目录访问协议的机制,实现了SOAP消息缓存模块,弥补了大量信息交换造成的系统效率降低。三是对新型应用和数据,通过动态代理模式,实现了对不同类型应用和数据的包装。
本文的创新之处在于,将知识系统与SOAP技术融合;通过Wrapper机制实现动态注册轻松实现系统集成;通过LDAP高速缓存消息达到提高系统效率的目的。
本文首先讨论了该课题的背景、需求及其研究意义,比较了国内外现有的技术和应用,探讨了将SOAP服务与知识系统结合的可行性。然后提出了基于二者的应用程序集成模型,并探讨每个模块的实现方法和关键技术。本文针对实例应用在第四章描述了模型核心模块的实现细节。最后,在第五章做出了总结和下一步展望。
This paper mainly focuses on building a n-tier integration Model for allowing thin clients using XML lathered in soap to access SOAP and legacy applications by using the architecture of Knowledge-Based System (KBS). SOAP is the kernel communication protocol of Web Service, which much help set up a connection rule between different kind of applications . The shortcoming of the architecture of web service is that it is lack of central control. On the contrary, KBS has the central control of its components. However, many KBSs is now facing the challenge of new techniques and is in danger of out-of-date. Therefore, it will be very meaningful to bring out a new architecture model that avoids the shortcomings of KBS and Web Service Architecture. And SOAP is the key to solve this problem and realize this model.
The main task of this paper is list as follows: Register dynamically the wrappers that wrapper different kind of legacy applications and control them; Realize SOAP cache and security mechanism by using OpenLDAP and JNDI. For SOAP applications, we use dynamic proxy factory to realize the integration.
This paper makes some contributions on bringing out the architecture that combines SOAP service and Knowledge-Based System, especially setting up criterions for dynamically registering wrappers that wrapper legacy application.
This paper firstly discusses the background, needs and meaningfulness of this subject, and then analyzes the research status abroad and homeland thereby draws conclusion on the possibility of combining SOAP and KBS. And then by using sample applications, we bring out an integration architecture model and discuss the means and techniques of the realization of each module.
引文
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