使用UML扩展机制描述软件非功能需求的新方法

指出了已有非功能需求描述方法的缺陷,提出了一种使用UML扩展机制描述非功能需求的新方法——NFR Profile,使非功能需求的描述更加直观和准确。同时,NFR Pronle将UML从功能建模扩展到非功能建模,丰富了UML的应用范围,使得对功能和非功能的建模可以统一在同一种建模语言和同一个建模工具中。     

带OCL的活动图多态性测试用例生成方法

研究UML活动图多态性测试用例的生成方法。形式化定义活动图,结合由类图、OCL约束和Liskov替换原则确定的多态性方法类集,扩展活动图中含多态信息的节点,得到多态扩展活动图。利用测试路径构造方法和覆盖准则,对多态扩展活动图进行遍历,生成测试用例。实验结果表明,该方法能生成含多态性信息的测试用例,提高测试覆盖度。     

Validation of requirement models by automatic prototyping

Prototyping is an efficient and effective way to understand and validate system requirements at the early stage of software development. In this paper, we present an approach for transforming UML system requirement models with OCL specifications into executable prototypes with the function of checking multiplicity and invariant constraints. Generally, a use case in UML can be described as a sequence of system operations. A system operation can be formally defined by a pair of preconditions and postconditions specified using OCL in the context of the conceptual class model. By analyzing the semantics of the preconditions and postconditions, the execution of the operation can be prototyped as a sequence of primitive actions which first check the precondition, and then enforce the postcondition by transferring the system from a pre-state to a post-state step by step. The primitive actions are basic manipulations of the system state (an object diagram), including find objects and links, create and remove objects and links, and check and set attribute values. Based on this approach, we have developed a tool of automatic prototype generation and analysis: AutoPA3.0.     

一种平衡Use Case需求模型复杂性的方法及应用

UML的Use Case模型由Use Case图和OCL描述两部分构成。设计者可在模型中使用较大的用例和较少的用例间的联系．形成较简单的用例图和较复杂的OCL描述，也可使用较复杂的用例图和较简单的OCL描述。介绍一种在用例图复杂性和OCL描述文档复杂性之间平衡的方法．需要时，可对用例图进行分解和规约，而不改变原模型的性质；同时介绍方法的一种应用．该应用也可作为独立的方法为建模提供帮助。     

基于UML OCL、支持团队开发的企业组织元模型

组织模型不仅要支持传统的纵向的组织结构,而且还要支持以团队方式工作的横向组织结构。本文提出了包含组织纵向和横向结构的组织元模型,并采用UML对象约束语言(OCL)描述了元模型中实体与实体之间的联系和约束关系。除用OCL描述组织结构外,还显式地给出了组织规则的OCL表示方法。这样,便可将组织规则与组织结构相分离,从而在组织结构不变的情况下,通过修改组织规则,以达到提供企业敏捷性的目的。     

Assessing the influence of import-coupling on OCL expression maintainability: A cognitive theory-based perspective

The aim of this paper is to present the definition of the measures for the import-coupling of OCL expressions, along with the empirical validation of these as early indicators of the maintainability of OCL expressions. This empirical validation has been carried out by means of an experiment and its replica, conducted with undergraduate students of Spanish and Argentinean universities, respectively. To perform this experimental activity, we have followed a cognitive theory-based approach, since the understanding of the cognitive demands that OCL expressions place on software engineers will allow us to examine in greater depth the real influence of import-coupling on the maintainability of OCL expressions. The empirical results, obtained through the analysis of the data from the experiment and its replica, first of all separately and then together after a meta-analysis study, reveal evidence suggesting that import-coupling exerts a certain amount of influence on the comprehensibility and modifiability of OCL expressions. The measures that have most influence on OCL expression comprehensibility are those related to problem objects (Number of Navigated Relationships (NNR), Weighted Number of Navigations (WNN), Depth of Navigations (DN) and Number of Attributes referred through Navigations (NAN)), relationships between problem objects (Number of Navigated Classes (NNC) and Number of Explicit Iterator variables (NEI)), as well as reified objects (Weighted Number of Collections Operations (WNCO)). On the other hand, it is only measures related to relationships between problem objects that are the main influence on OCL expression modifiability. The influence of import-coupling on the comprehensibility and modifiability of OCL expressions was reaffirmed through the cognitive complexity (i.e. we show that import-coupling affects the cognitive complexity and that the latter influences the comprehension and modification of OCL expressions). These results may have educational implications, apart from what they might mean for practitioners in the industry, as is explained in the conclusions.     

面向方面的CORBA模型

AOP在打破实体封裳性和表达横切实体间的非功能性需求的能力上得到了广泛地认可.并在越来越多的实际项目中获得成功.然而文献[1]模型描述语义的OMG IDL不能完整表述.通过讨论AOP与文献[1]描述模型中OCL的关系,以及通过AOP的UML扩展来讨论建立面向方面的CORBA模型的方法.可认为AOP技术为CORBA模型到语言的对应提供一种途径.     

基于模型转换实现行为协议的研究

为平台无关的UML模型元素(如类、接口)增加行为协议通常没有有效的解决方法。提出了一种基于模型转换实现行为协议的方法,编写了模型转换规则将状态机描述的行为协议元数据自动转换为UML操作元素的约束,运用OCL验证器和代码生成器对转换后的UML模型进行自动验证和代码生成。该方法为行为协议的自动验证、与模型元素同步和规范的正确实施提供了有效支持。     

An approach to test-driven development of conceptual schemas

Test-Driven Development (TDD) is an extreme programming development method in which a software system is developed in short iterations. In this paper we present the Test-Driven Conceptual Modeling (TDCM) method, which is an application of TDD for conceptual modeling, and we show how to develop a conceptual schema using it. In TDCM, a system's conceptual schema is incrementally obtained by performing three kinds of tasks: (1) Write a test the system should pass; (2) Change the schema to pass the test; and (3) Refactor the schema to improve its qualities. We also describe an integration approach of TDCM into a broad set of software development methodologies, including the Unified Process development methodology, the MDD-based approaches, the storytest-driven agile methods and the goal and scenario-oriented requirements engineering methods. We deal with schemas written in UML/OCL, but the TDCM method could be adapted to the development of schemas in other languages.