【作者】 彭钰；

【导师】 钟珞；

【作者基本信息】 武汉理工大学 ， 计算机应用技术， 2006， 硕士

【摘要】 作为一个新兴的研究领域,工作流技术已经被广泛应用于生产制造、办公自动化、并行工程、电子政务等领域,是实现企业业务过程建模、优化、过程管理与集成,最终实现业务过程自动化的核心技术。工作流技术的实施已经成为企业完善经营过程、提高自身竞争力的一种重要手段。Petri网系统是一种适合于描述异步并发现象的计算机模型,具有坚实的理论基础和成熟的分析技术,利用Petri网建立的模型有着良好的直观图形和有力的分析技术支持,因此可以使用Petri网对工作流建立模型,使得建立的工作流过程既明显直观,又可以保证过程的正确性。 本文研究了工作流技术在公文流转系统中的应用,结合实际应用环境,选择Petri网作为工作流建模的工具,将工作流的路由结构、触发机制引入到建模过程中,提出了一个基于Petri网的公文流转工作流模型,并且将Petri网三要素以对象的形式描述出来,进而将整个流程以三个列表表示,成为程序语言可以识别的形式,使流程的自定义成为可能。为了增强公文流转系统的实用性和安全性,系统从两个方面考虑:第一方面,Petri网模型,必须使用高级Petri网对工作流过程进一步的建模。分别引入时间Petri网和有色Petri网。时间Petri网可以满足实例运行中对于时间约束的要求,通过增加时间约束模块模型来实现。着色Petri网可以区分同时运行的不同实例。第二方面Java的安全性技术分析,对公文流转中的文件进行加密并且签名,从而实现信息的真实性、完整性、保密性和不可否认性。系统提供了较强的安全机制,保证实例运行时候的安全。然后介绍了当今流行的基于Java技术的B/S三层架构的开发模式,JSP处理表示层,Java bean实现系统模块较为复杂的功能,Servlet控制协调表示层和逻辑层。在实现常见OA功能的前提下,系统的安全模块实现内外结合的安全策略(即外部以CA证书验证,内部以权限控制为主的安全策略)。更多还原

【Abstract】 Workflow technology, as a new research field, has being widely applied in the fields of manufacturing, office automation, concurrent engineering, electronic government and so on. It is the key technology to realize modeling, optimizing, managing and integrating of enterprises’ business process and also the automation of business process. The workflow technology has become an important method to smooth the business process and improve the competitiveness of enterprises.Petri Nets System is an advanced tool to describe asynchronies computing model, since that time it has been studied in depth, and possess stability theory basis and analyses technology. A workflow model based on Petri Net can be frankly examined and powerful supported a model of workflow process, so it can be provided distinct and correct.This paper researches the application of Workflow technology in Official Document System, according to the actual conditions, Petri-net was chosen as a tool for Workflow modeling, and its route structure and trigger mechanism of Workflow were introduced to the modeling course. Moreover, three key elements of Petri-net were described in the form of object, and the whole procedure was expressed by three lists, which can be recognized by program language, therefore makes it possible for procedure self defining.In order to increase practicability and security of the Official Document System, two parts are considered: the first is Petri Net, HLPN(High-Level Petri Net) was injected, Time Petri Net and Colored Petri Net. Time Petri Net can solve restriction of time of running process, via adding a time restriction model. After using Colored Petri Net, the system can distinguish different kinds of instance. The second is Java security machine, it can encrypt electronic files and provide digital signature, with the support of this technology, the system achieves its confidentiality, integrity, privacy, and non-repudiation. The archetype system achieved typical functions of a workflow management system, as well as implement of security on activities’ execution.Then, we introduce the B/S designing mode based on the Web technologies of Java, The JSP handles the presentation layer, the Javabean realizes the complicatedfunction of some modules and the Servlet controls the collaboration between the presentation layer and the logical layer. The aim for developing this system is to realize the common functions of the OA system and further it attempts to realize the information security scheme that will have a mixed security policy, which can provide external CA security service and the role based access control function within this system.更多还原