【作者】 刘宏；

【导师】 陈传波；

【作者基本信息】 华中科技大学 ， 软件工程， 2005， 硕士

【摘要】 软件复用的理论和实践尚未彻底解决三个基本问题:是否存在大量的可复用对象; 如何判断所复用对象的有用性; 复用者怎样去使用被复用的对象。这三个基本问题都与“软件复用中的变化点”问题相关。引入关系数据理论的函数依赖作为数学工具,探讨软件复用中的变化点问题,并应用到设计模式和EntityBean 的组件体系接口规范的范畴。这个数学工具的引入,对于软件的成功复用既非充分条件也非必要条件,但是对于变化点这个问题来说具有说明和“强调”的意义。关系数据理论中的规范化思想是逐步消除数据依赖中不合理的部分,使各关系模式达到某种程度的“分离”,即“一事一地”的模式设计原则。让一个关系描述一个概念、一个实体或者实体间的一种联系。若多于一个概念就把它“分离”出去。因此所谓规范化实质上是概念的单一化。复用驱动的软件工程业务(RSEB)是经过瑞典爱立信公司的AXE 项目实践检验的。基于RSEB 的软件复用从用例组件开始实行变化点和变体的跟踪,直至实现对于组件的复用。引入关系模式的部分依赖和传递依赖关系是分析软件复用中变化点问题的一种方法,本文简称VRFD 方法。作为VRFD 方法的理论基础,本文讨论了关于“第一范式”的问题,讨论了变化点与部分依赖和传递依赖的关系。在此理论基础上,本文将这种分析方法应用到设计模式和EJB 组件体系接口规范进行讨论。将VRFD 方法应用到设计模式。讨论了类继承、接口继承,以及面向对象方法中抽象和封装变化点的概念。讨论了若干个设计模式,分别在各个模式的讨论中逐步深入,涉及部分依赖和传递依赖以及两种依赖的“一致性”问题,并过渡到“责任分离”的概念。然后讨论了关于学习设计模式的问题。将VRFD 方法应用到EJB 组件体系接口规范。对EJB 组件体系接口规范的基础部分Java RMI 进行了讨论; 使用“责任的分离和分派”来讨论EntityBean 组件体系接口规范的设计,它是讨论软件复用中的变化点的直观方式。VRFD 方法引入关系数据理论的函数依赖来分析软件复用中变化点的问题,并指出“处理变化点”和“责任的分离和分派”是两个等价的概念; 通过引入形式化的语言,对软件复用中在这方面存在的问题进行了深入的剖析和揭示。更多还原

【Abstract】 There are three fundamental problems that have not been solved in theory as well as in practice about Software Reuse: Whether do the masses of reusable components exist? How to identify the usability of the reused components? How to use the reused components? These three problems are relevant to the concept of Variation Point in Software Reuse. The Normalization Theory with Relational Data system, especially Functional Dependencies Theory is introduced to research the problems of Variation Point in Software Reuse. They are applied to Design Patterns and the Specification of the interfaces of Component Model in EntityBean on the next. While they are NOT Sufficient Condition and NOT Necessary Condition for the success of Software Reuse, they are meaningful to show and emphasis the problems of Variation Point in Software Reuse. The thought of Normalization in Relational Data system is to eliminate the improprieties in Data Dependencies with steps, that is, to some extents, to partition the Relation Schema, as well as the principle of design patterns in schema, One Thing One Place. That is, make a Relation with one conception, or one entity, or one relationship between the entities. So, if there is more than one conception in a Relation, they should be partitioned. In a word, Normalization is essentially the simplification of conceptions. The Reuse-Driven Software Engineering Business (RSEB)has been practiced in AXE,Ericsson,Sweden. Software Reuse based on RSEB traces the variation points and the corresponding varieties from UseCase components to the end-point where the components and the varieties are reused. A Method to Study on Variation Point in Software Reuse Based on Functional Dependency,called VRFD, is introduced. In theory, the problem of the first Normal Form is discussed firstly, and the following are the relationships between two respective Dependencies, Partial Dependency and Transfer Dependency, and Variation Point. On the bases of the theoretical study, the method is applied to Design Patterns and the Specification of the interfaces of Component Model in EntityBean. VRFD is applied to Design Patterns. First of all are the conceptions of Class Inheritance, Interface Inheritance, Abstraction and Encapsulation in the Object-Oriented Method. The following are 9 design patterns. With these design patterns, the discussion goes into further depth, talking about both the partial dependencies and the transfer dependencies; further more, the CONSISTENCY about the two Dependencies is explored. Then the transition to the conception of Responsibility-Partition is accomplished. At last is the opinion of studying Design Patterns. Applying VRFD to the Specification of the interfaces of Component Model in EntityBean is the end. While EJB is defined to be a distributed computing architecture based on Component, Java RMI, which is a fundamental part of EJB, is discussed. Then the conception of Responsibility-Partition is used to research the Specification of the interfaces of Component Model in EntityBean, which is the intuitive way to handle Variation Point in Software Reuse. Introducing Functional Dependency in Relational Data system to research the problem of Variation Point in Software Reuse, VRFD point out the equivalence of the two conceptions, handling the Variation Point with VRFD and Responsibility-Partition. Further more, with formalization language introduced, the problem of Variation Point in Software Reuse is explored in-depth.更多还原