面向方面的实时系统开发方法 郭东亮毕业论文最终稿

广东工业大学工学硕士学位论文面向方面的实时系统开发方法郭东亮二零零五年四月三十日分类号：学校代码：11911 UDC：密级：学号：2110205159广东工业大学学位论文面向方面的实时系统开发方法郭东亮指导教师：张立臣教授广东工业大学计算机学院学科门类：工学专业名称：计算机软件与理论申请学位级别：硕士论文提交日期： 2005 年 4 月论文答辩日期： 2005 年 5 月学位授予单位：广东工业大学摘要现代软件开发都要把整个系统按功能分解为小的单元，然后开发这些小单元，这些小的单元隐藏内部实现，对外提供接口，最后组合这些单元为整个系统，实现整个系统的功能。

但是系统中有的方面是横切整个系统的非功能关注点，无法很好地封装在单个模块中。

如日志、性能问题、安全、上下文相关错误处理、QoS 监测等等，这些方面分散在整个系统中，并且与系统的功能代码纠缠在一起，这样降低了模块的可追踪性、模块的可重用性、系统的可维护性等一系列问题，所以需要分离并模块化这些非功能关注点。

面向方面编程在实现上分离和模块化横切关注点，面向方面建模在软件开发的其它阶段用一致的方法来详述、可视化、构造和文档化方面相关制品，这样在整个软件开发过程可以使用面向方面技术。

实时系统是面向方面技术很好的应用场所，因为在实时系统中，有很多非功能需求，且这些非功能需求往往横切整个系统。

在实时系统中关键的就是时间要求了，这些时间要求散布在整个系统的功能部件里，带来了代码混乱和代码分散问题。

本文分析介绍了AspectJ、组合过滤器、多维关注点分离和自适应编程等典型的分离关注点的方法。

比较完整的介绍了面向方面建模领域的研究。

阐述了实时系统中的主要实时需求，以及与实时系统有关的UML框架集。

提出了一个新的扩展UML进行面向方面建模的方法，它以合适的语义表达了AspectJ和AspectC++的元素和织入机制。

在这个方法中，方面继承自类，切入点和通知继承自特征，这样切入点和通知是方面的一部分，方面与基本类的关系用横切依赖表示。

切入点的图符可以表达多个方面在相同连接点的横切行为，通知以一致的方式建模结构横切和行为横切，通过在顺序图上新加一个通知发出焦点，并将通知表示为消息，这样可以清晰建模通知在何时何处怎样影响系统的行为。

并分析了如何将这个方法应用于实时系统开发。

关键词：面向方面编程；面向方面软件开发；实时系统；UMLAbstractUsing modern software development methodology, developers first decompose system into small units, which hide the internal implementation and provide only external interfaces, then implement these units, at last compose these units to get a full system and realize required functions. But there are some non-functional concerns which crosscut whole system and can’t be well encapsulated into a single module, such as logging, performance analysis, security, context related error handling, QoS monitoring, etc. These aspects are scattered and tangled in whole system, decreasing software traceability, reusability, adaptability. So these non-functional concerns should be separated and modularized.Aspect-Oriented Programming (AOP) separates and modularizes crosscutting concerns at implementation stage. Aspect-Oriented Modeling (AOM) specifies, visualizes, constructs and documents aspect related artifacts in a consistent way at other stage of software development. Thus whole software development process can use aspect-oriented technique.Real-time systems are well places to apply aspect-oriented technique, for there are lots of non-functional requirements in real-time system, which scattering in whole system. The codes related with timing are mixed with other codes, resulting in code scattering and tangling.This article considers various techniques to separate crosscutting concerns, namely AspectJ, AspectC++, Composition Filters, Hyperspace and Adaptive Programming; summarizes the researches in AOM domain; analyses real-time systems timing requirements and UML profiles for real-time systems.This article proposes a new technique to modeling aspect-oriented constructs and mechanisms by extending UML, which can represent constructsand weaving mechanism of AspectJ and AspectC++ with appropriate semantics. In this method, aspect is subclass of class; pointcut and advice are derived from feature, thus pointcut and advice are parts of aspect; relationship between aspects and base class is represented by special crosscut dependency. The notation of pointcut can express crosscutting behavior of many aspects at same join point. Advice can model structural crosscutting and behavior crosscutting in a uniform way. By adding a new block, advice sending focus, in sequence diagram and regard advice as message, this method can clearly model where and when and how advices affect system behavior. The article also examines how this technique can be practiced in real-time systems development.Keywords: AOP；AOSD；real-time systems；UML目录摘要 (I)Abstract (II)目录 (V)Contents................................................................................................................. V II 第一章绪论 (1)1.1 研究背景 (1)1.2研究意义 (2)1.3面向方面技术在实时系统中的应用 (3)1.4 研究内容 (4)第二章分离关注点的方法 (5)2.1 AspectJ (5)2.2 AspectC++ (7)2.3 组合过滤器 (8)2.4 Hyperspace (13)2.4.1 多维关注点分离 (13)2.4.2 Hyperspace (15)2.4.3 Hyper/J (16)2.5自适应编程 (17)第三章实时系统软件设计 (21)3.1 实时系统概念 (21)3.2 实时需求 (21)3.3 实时UML扩展 (23)3.3.1 通用资源建模 (25)3.3.2 通用时间建模 (30)3.4 实时系统建模工具 (34)第四章面向方面建模 (35)4.1 UML的扩展机制 (35)4.2 表示连接点 (36)4.3用况实现模块化 (36)4.4用UML进行面向方面建模 (37)第五章实时方面建模 (39)5.1 AOP元素表示 (39)5.1.1表示切入点 (39)5.1.2表示通知与引入 (40)5.1.3 表示方面 (41)5.2 举例 (41)5.3 用况实现模块化 (44)5.4 在类图中加入方面 (45)5.5在顺序图中加入方面 (47)5.6 其它 (50)结论 (51)参考文献 (53)攻读硕士学位期间发表的论文 (58)独创性声明 (59)致谢 (61)ContentsAbstract (II)Contents .................................................................................................................. V II Chapter1 Introduction .. (1)1.1 Background (1)1.2 Necessity (2)1.3 Aspect-Oriented Technique in Real-time Systems (3)1.4 Structure of this Thesis (4)Chapter2 Approaches to Separate Concerns (5)2.1 AspectJ (5)2.2 AspectC++ (7)2.3 Composition Filters (8)2.4 Hyperspace (13)2.4.1 MDSOC (13)2.4.2 Hyperspace (15)2.4.3 Hyper/J (16)2.5 Adaptive Programming (17)Chapter3 Real-time Systems Software Design (21)3.1 Concepts of Real-time System (21)3.2 Timing Requirements (21)3.3 UML Extension for Real-time System (23)3.3.1 General Resource Modeling (25)3.3.2 General Timing Modeling (30)3.4 Tools for Real-time System Modeling (34)Chapter4 Aspect-Oriented Modeling (35)4.1 UML Extension Mechanism (35)4.2 Join Point Representation (36)4.3 Use Case Modularity Using AOSD (36)4.4 Aspect-Oriented Modeling Using UML (37)Chapter5 Real-time Aspect Modeling (39)5.1 Modeling Constructs of AOP (39)5.1.1 Modeling Pointcut (39)5.1.2 Modeling Advice and Introduction (40)5.1.3 Modeling Aspect (41)5.2 Example (41)5.3 Modularizing Implementation of Use Case (44)5.4 Adding Aspect to Class Diagram (45)5.5 Adding Aspect to Sequence Diagram (47)5.6 Others (50)Summary and Future Work (51)Bibliography (53)Publications During Master's Studies (58)Statement of Originality (59)Acknowledgments (61)第一章绪论1.1 研究背景软件开发思想就是抽象与分解，从过程化、结构化分解编程，到现在主流的面向对象编程，开发典范（paradigm）发生了很大变化，唯一不变的就是抽象与分解的思想，只是抽象的种类和质量、分解的方法发生了变化。