基于面向方面编程方法的研究

面向方面编程方法是一种新的程序开发方法,主要是为了弥补面向对象方法的一些不足。该文介绍了面向方面编程的基本概念、语法规范,并且以面向方面语言Aspectj为例说明面向方面编程的特点。     

软件可修改性在软件开发过程中的控制*

在传统的软件可修改性定义的基础上提出了基于软件开发过程的软件可修改性,确定了垂直软件可修改性和水平软件可修改性的关系和基本度量方法。建立了基于软件开发过程的软件可修改性模型,得到了软件开发过程各阶段中软件可修改性的度量方法,从而为在软件开发过程中控制软件的可修改性提供了基础。     

面向方面的软件体系结构描述语言AO-ADL

分析面向方面编程(AOP)的核心思想及其优越性,将编码阶段的AOP概念进一步提升到软件体系结构层次。在软件体系结构描述语言XYZ/ADL的基础上,通过增加新的元素和相关复合机制,得到一种面向方面的体系结构描述语言AO-ADL,实现了在软件体系结构中横切功能的模块化。     

软件开发流程方法探析

首先对国内外软件开发理论的应用现状作了比较,然后重点分析软件系统开发流程,综合分析比较软件开发流程的各个阶段.     

Components meet aspects: Assessing design stability of a software product line

Context

It is important for Product Line Architectures (PLA) to remain stable accommodating evolutionary changes of stakeholder’s requirements. Otherwise, architectural modifications may have to be propagated to products of a product line, thereby increasing maintenance costs. A key challenge is that several features are likely to exert a crosscutting impact on the PLA decomposition, thereby making it more difficult to preserve its stability in the presence of changes. Some researchers claim that the use of aspects can ameliorate instabilities caused by changes in crosscutting features. Hence, it is important to understand which aspect-oriented (AO) and non-aspect-oriented techniques better cope with PLA stability through evolution.

Objective

This paper evaluates the positive and negative change impact of component and aspect based design on PLAs. The objective of the evaluation is to assess how aspects and components promote PLA stability in the presence of various types of evolutionary change. To support a broader analysis, we also evaluate the PLA stability of a hybrid approach (i.e. combined use of aspects and components) against the isolated use of component-based, OO, and AO approaches.

Method

An quantitative and qualitative analysis of PLA stability which involved four different implementations of a PLA: (i) an OO implementation, (ii) an AO implementation, (iii) a component-based implementation, and (iv) a hybrid implementation where both components and aspects are employed. Each implementation has eight releases and they are functionally equivalent. We used conventional metrics suites for change impact and modularity to measure the architecture stability evaluation of the 4 implementations.

Results

The combination of aspects and components promotes superior PLA resilience than the other PLAs in most of the circumstances.

Conclusion

It is concluded that the combination of aspects and components supports the design of high cohesive and loosely coupled PLAs. It also contributes to improve modularity by untangling feature implementation.     

Dynamic architectures for microcomputers

This paper describes low cost dynamic architectures for microcomputers. The proposed architectures allow the CPU to be simultaneously active during DMA block I/O operations. As a result, a considerable speed advantage may be obtained at very little extra cost. An experimental system has been built and successfully tested. Several computational environments have been simulated on the prototype system. Some alternative designs with varying degrees of flexibility and hardware cost are discussed. The designs are aimed primarily at total overlap of I/O interfaces and processor activities. Emulation data show that in many application environments the proposed architectures could provide substantially higher throughputs than conventional static architectures.     

Why Aspect-Oriented Software Development And Model-Driven Development Are Not The Same – A Position Paper –

Aspect-Oriented Software Development (AOSD) and Model-Driven Development (MDD) are often said to be alike since both approaches are based on the selection of elements (i.e. join points in AOSD and model elements in MDD) and their subsequent adaptation (i.e. weaving in AOSD and transformation in MDD). But does this mean that AOSD and MDD are in fact two words for pretty much the same thing? In this position paper, we argue that there are essential differences between the aspect-oriented and the model-driven approach.     

ArchiMeDeS: A model-driven framework for the specification of service-oriented architectures

This paper presents a framework for the Model-Driven specification of Software Architectures, which is defined using the concepts behind Service-Orientation. The framework described, denominated as ArchiMeDeS, represents the following: a coherent solution to the problem of architecting the existing gap between the high-level configuration of a software system by describing the business entities and relationships required by a software solution, and its low-level representation, in which the technological aspects determine the final shape of the system, providing technical support to the previously identified business processes and constraints. We also provide a set of transformation rules, which semi-automatically advance in the Architecture specification. These rules allow progress to be made from conceptual architectural models to more technologically dependent ones. The feasibility of the proposed service-oriented framework is validated by showing its usage capabilities in the definition of a software solution in the field of neuroscience research.     

Specifying redundancy tactics as crosscutting concerns using aspect-oriented modeling

Various redundancy tactics can be modeled at the design stage of safety-critical systems thereby providing a set of fault-tolerance guidelines for subsequent development activities. However, existing approaches usually interweave redundancy tactics into the functional models making them complex and cluttered; the maintenance of such models is time-consuming and error-prone. To address this problem, we provide a modeling approach to separate the redundancy tactics from the base functional models using aspect-oriented modeling. More specifically, the conceptual models of the redundancy tactics and their semantic constraints are first defined for deriving the relevant aspects. Subsequently, a UML profile is proposed to specify the tactic aspects followed by mapping these concepts to the corresponding concepts of aspect-oriented modeling based on pre-defined principles. In accordance with our proposed profile, reuse directives are applied to handle the overlap of structural features between redundancy tactics and other kinds of tactic. Based on our tactic aspects and their configured attributes, a weaving algorithm is proposed to associate the tactic aspects with the base functional models. The proposed approach is compared with a traditional tactic modeling approach using two safety-critical systems, revealing that: 1) our approach significantly reduces the number of extra model elements needed in the tactic design stage; 2) our approach can largely avoid the impact of changing of the base functional model as the model evolves.     

流程结构复杂性量度分析及其应用

本文以目前常用的Ｃ／Ｃ＋＋语言作为背景语言，对语句组合结构和自定义函数调用结构应用图工具进行了复杂性量度分析。对语句组合结构复杂性更进一步作了实例的量度值统计和应用性分析。     

Specifying redundancy tactics as crosscutting concerns using aspect-oriented modeling

Various redundancy tactics can be modeled at the design stage of safety-critical systems thereby providing a set of fault-tolerance guidelines for subsequent development activities. However, existing approaches usually interweave redundancy tactics into the functional models making them complex and cluttered; the maintenance of such models is time-consuming and error-prone. To address this problem, we provide a modeling approach to separate the redundancy tactics from the base functional models using aspect-oriented modeling. More specifically, the conceptual models of the redundancy tactics and their semantic constraints are first defined for deriving the relevant aspects. Subsequently, a UML profile is proposed to specify the tactic aspects followed by mapping these concepts to the corresponding concepts of aspect-oriented modeling based on pre-defined principles. In accordance with our proposed profile, reuse directives are applied to handle the overlap of structural features between redundancy tactics and other kinds of tactic. Based on our tactic aspects and their configured attributes, a weaving algorithm is proposed to associate the tactic aspects with the base functional models. The proposed approach is compared with a traditional tactic modeling approach using two safety-critical systems, revealing that： 1） our approach significantly reduces the number of extra model elements needed in the tactic design stage; 2） our approach can largely avoid the impact of changing of the base functional model as the model evolves.     

基于AOP的软件运行轨迹捕获技术研究与实现

借助面向方面编程（AOP）的关注点分离思想,提出了基于AOP的软件运行轨迹捕获技术,它能在不改变源代码的情况下为系统注入运行轨迹捕获和运行行为监测功能,从而有效提高系统中监控模块的松耦合性。以该技术为基础实现了系统运行轨迹分析工具SRT,该工具能够在改善系统模块性的同时,为软件轨迹监测、系统故障定位提供量化依据与可信性保障。     

以“项目教学法”促进“软件工程”教学

本文针对软件工程课程特点和在教学中存在的问题,提出用"项目教学法"提高软件工程教学质量,并在教学思想、理论教学和实验模式三个方面对该方法的实施作了详尽论述。     

CAD应用软件的二次开发

根据二次开发的特点，本文讨论了二次开发CAD在用软件时应遵循的原则，并进一步研究了参数化CAD、成组CAD、交互式CAD以及智能CAD应用软件的工作原理、开发方法、应用场合及各自的特点。此文对具体进行CAD应用软件的二次开发具有一定的指导意义。     

Quality management metrics for software development

It can be argued that the quality of software management has an effect on the degree of success or failure of a software development program. We have developed a metric for measuring the quality of software management along four dimensions: requirements management, estimation/planning management, people management, and risk management. The quality management metric (QMM) for a software development program manager is a composite score obtained using a questionnaire administered to both the program manager and a sample of his or her peers. The QMM is intended to both characterize the quality of software management and serve as a template for improving software management performance. We administered the questionnaire to measure the performance of managers responsible for large software development programs within the US Department of Defense (DOD). Informal verification and validation of the metric compared the QMM score to an overall program-success score for the entire program; this resulted in a positive correlation.     

A Systematic Approach to Metamodeling Environments and Model Transformation Systems in VMTS

Highly configurable metamodeling environments and graph transformation techniques have been applied successfully in software system modeling and other areas. In this paper a uniform treatment of these two methods is illustrated by a tool called Visual Modeling and Transformation System. The concepts of an n-layer metamodeling environment is outlined with the related topological and attribute issues. Built on metamodeling techniques two alternatives for model transformation are elaborated, namely, the traversal and the graph-rewriting approaches. In our implementation all of the aforementioned mechanisms use metamodel as a common formalism, which can be considered as a uniform basis for storing, creating and transforming visual languages. The feasibility of the approach is illustrated by a transformation which generates C/C++ code from UML statecharts.     

Stability assessment of aspect-oriented software architectures: A quantitative study

Design of stable software architectures has increasingly been a deep challenge to software developers due to the high volatility of their concerns and respective design decisions. Architecture stability is the ability of the high-level design units to sustain their modularity properties and not succumb to modifications. Architectural aspects are new modularity units aimed at improving design stability through the modularization of otherwise crosscutting concerns. However, there is no empirical knowledge about the positive and negative influences of aspectual decompositions on architecture stability. This paper presents an exploratory analysis of the influence exerted by aspect-oriented composition mechanisms in the stability of architectural modules addressing typical crosscutting concerns, such as error handling and security. Our investigation encompassed a comparative analysis of aspectual and non-aspectual decompositions based on different architectural styles applied to an evolving multi-agent software architecture. In particular, we assessed various facets of components’ and compositions’ stability through such alternative designs of the same multi-agent system using conventional quantitative indicators. We have also investigated the key characteristics of aspectual decompositions that led to (in)stabilities being observed in the target architectural options. The evaluation focused upon a number of architecturally-relevant changes that are typically performed through real-life maintenance tasks.     

基于CMM的软件开发过程研究

通过建立一致的、标准的软件开发过程,软件开发组织可以提高对软件项目开发的控制性和预见性,并可提高其开发效率。CMM通过实践证明可以有效提高软件开发组织的生产能力和产品质量,它强调角色的划分,按角色分配任务。同时,它的过程划分是基于改进的V瀑布模型,突出软件测试的重要性。     

公共卫生信息平台软件工程化开发探讨

本文讲述了在公共卫生信息平台项目的开发过程中采用软件工程化方法和技术进行平台的开发。分析了软件工程化开发现状及需求,探讨了软件工程化目标和软件工程化技术路线,并给出了软件工程化开发步骤。