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941.
软件系统的活性和安全性是判断软件可演化性的重要依据之一。现有方法多使用经典逻辑对系统的活性和安全性进行刻画。环境及涉众的复杂性使得软件的可演化性分析可能出现矛盾的输入。经典逻辑的无矛盾律导致其不能对软件系统的演化特性进行有效建模。针对该问题,提出了一种形式化的软件可演化性特征描述方法,该方法允许矛盾性输入的存在,可用于对软件可演化性等存在矛盾特性的系统进行建模和分析。该方法使用多值时序逻辑刻画软件系统的演化需求,同时提出了一种抽象软件模型对软件系统进行建模,通过抽象软件模型的活性和安全性来对软件系统的可演化特征进行描述。 相似文献
942.
设计模式在GIS软件开发中的应用研究 总被引:15,自引:2,他引:15
详细论述了组合(Composite)、桥接(Bridge)、观察者(Observer)、命令(Command)、外观(Facade)、装饰(Decora-tor)六种设计模式在GIS软件开发中的应用。旨在促使GIS开发中注重设计模式,努力发现、归纳并应用设计模式,实现软件设计的重用,提高GIS软件的质量和开发效率。 相似文献
943.
本文主要介绍Sun Openwindows Developer’s Guide3.0.1软件的简单使用和主要特点。 相似文献
944.
This paper describes an approach to the formalization of existing criteria used in computer systems software testing and proposes
a new Reinforced Condition/Decision Coverage (RC/DC) criterion. This new criterion has been developed from the well-known
Modified Condition/Decision Coverage (MC/DC) criterion and is more suitable for the testing of safety-critical software where
MC/DC may not provide adequate assurance. As a formal language for describing the criteria, the Z notation has been selected.
Formal definitions in the Z notation for RC/DC, as well as MC/DC and other criteria, are presented. Specific examples of using
these criteria for specification-based testing are considered and some features are formally proved. This characterization
is helpful in the understanding of different types of testing and also the correct application of a desired testing regime.
Received July 2004
Revised November 2005
Accepted November 2005 by J. Derrick, M. Harman and R.M. Herons 相似文献
945.
946.
ContextReflexion Modelling is considered one of the more successful approaches to architecture reconciliation. Empirical studies strongly suggest that professional developers involved in real-life industrial projects find the information provided by variants of this approach useful and insightful, but the degree to which it resolves architecture conformance issues is still unclear.ObjectiveThis paper aims to assess the level of architecture conformance achieved by professional architects using Reflexion Modelling, and to determine how the approach could be extended to improve its suitability for this task.MethodAn in vivo, multi-case-study protocol was adopted across five software systems, from four different financial services organizations. Think-aloud, video-tape and interview data from professional architects involved in Reflexion Modelling sessions were analysed qualitatively.ResultsThis study showed that (at least) four months after the Reflexion Modelling sessions less than 50% of the architectural violations identified were removed. The majority of participants who did remove violations favoured changes to the architectural model rather than to the code. Participants seemed to work off two specific architectural templates, and interactively explored their architectural model to focus in on the causes of violations, and to assess the ramifications of potential code changes. They expressed a desire for dependency analysis beyond static-source-code analysis and scalable visualizations.ConclusionThe findings support several interesting usage-in-practice traits, previously hinted at in the literature. These include (1) the iterative analysis of systems through Reflexion models, as a precursor to possible code change or as a focusing mechanism to identify the location of architecture conformance issues, (2) the extension of the approach with respect to dependency analysis of software systems and architectural modelling templates, (3) improved visualization support and (4) the insight that identification of architectural violations in itself does not lead to their removal in the majority of instances. 相似文献
947.
948.
YE Miao 《数字社区&智能家居》2008,(14)
构件技术成为当前软件工程中的发展方向,构件的软件测试成为软件测试中的一个新的研究领域。本文对构件技术做了简单的介绍后,对构件测试中遇到的困难和问题做了比较详细的描述,并介绍了目前过内外在构件测试方面的一些成果现状。 相似文献
949.
组态软件作为一种在工业上被广泛应用的可配置软件,其设计面临着过多的可变因素。通过在组态软件的开发过程中引入设计模式,可以简化组态软件的结构,提高代码的复用性,并能有效应对将来可能出现的变更。本文着重讨论了Adapter、Bridge、Observer三种设计模式在组态软件设计中的应用。 相似文献
950.
Daniel Kellyton Alexandre Vinicius Cardoso Eduardo Santana Renata Pontin Silvio Lemos 《Journal of Systems and Software》2008,81(6):996-1013
This paper aims at identifying some of the key factors in adopting an organization-wide software reuse program. The factors are derived from practical experience reported by industry professionals, through a survey involving 57 Brazilian small, medium and large software organizations. Some of them produce software with commonality between applications, and have mature processes, while others successfully achieved reuse through isolated, ad hoc efforts. The paper compiles the answers from the survey participants, showing which factors were more associated with reuse success. Based on this relationship, a guide is presented, pointing out which factors should be more strongly considered by small, medium and large organizations attempting to establish a reuse program. 相似文献