Introducing object orientation into large and complex systems

The paper investigates the applicability of the object-oriented technique to large and complex systems as exemplified by the operating system BS2000 which has been under constant development for a number of years. The proposed system architecture ensures the harmonious coexistence of procedural and object-oriented parts of the system. New domains, which are implemented using the object-oriented paradigm, can be smoothly embedded in the existing system. The parallel usage of different implementation languages is rendered economically viable. In our framework some representative parts of the system were redesigned and implemented in a prototype. The extensibility of the design was checked by including further parts into this scheme. The results are encouraging, so that the object-oriented technique will be used in the further development process. The proposed technique can also be applied to systems with a different structure, even a monolithic one     

装备虚拟试验系统体系结构及其互联技术

为满足大规模装备全系统、全功能、全范围、全要素的试验要求,采用试验与训练使能体系结构的设计思想,根据数据分发服务(DDS)系统的相关标准,提出一种新的虚拟试验系统体系结构。以大规模舰艇装备虚拟试验系统为例,分析其中各模块的主要功能,设计系统内部DDS信息分发中间件用例。应用结果证明,该体系结构适用于多种平台、多类系统和多型设备的装备虚拟试验环境建设。     

A graph mining approach for detecting identical design structures in object-oriented design models

The object-oriented approach has been the most popular software design methodology for the past twenty-five years. Several design patterns and principles are defined to improve the design quality of object-oriented software systems. In addition, designers can use unique design motifs that are designed for the specific application domains. Another commonly used technique is cloning and modifying some parts of the software while creating new modules. Therefore, object-oriented programs can include many identical design structures. This work proposes a sub-graph mining-based approach for detecting identical design structures in object-oriented systems. By identifying and analyzing these structures, we can obtain useful information about the design, such as commonly-used design patterns, most frequent design defects, domain-specific patterns, and reused design clones, which could help developers to improve their knowledge about the software architecture. Furthermore, problematic parts of frequent identical design structures are appropriate refactoring opportunities because they affect multiple areas of the architecture. Experiments with several open-source and industrial projects show that we can successfully find many identical design structures within a project (intra-project) and between different projects (inter-project). We observe that usually most of the detected identical structures are an implementation of common design patterns; however, we also detect various anti-patterns, domain-specific patterns, reused design parts and design-level clones.     

A novel open CNC architecture based on STEP-NC data model and IEC 61499 function blocks

Modern manufacturing industries demand computer numeric controllers, having higher level input languages than outdated G-code, and less proprietary vendor dependencies. IEC 61499 is a new standard for distributed measurement and control systems, that enables portability and interoperability of embedded controllers, along with the ease of their mapping to arbitrary distributed networking hardware configurations. This paper demonstrates that the IEC 61499 reference architecture can be successfully used to create a computer numeric controller, offering interoperability, portability, configurability, and distribution characteristics. The layered CNC-FB architecture is proposed, which simplifies the design of a CNC machine controller with the architecture layers responsible for data processing, data storage and execution. In combination with the object-oriented Model-View-Control design pattern, the CNC-FB architecture supports the design framework, in which simulation of the machining becomes natural and inherent part of the design process, with seamless transition from simulation to actual machining. The implemented controller was tested in both the model and on an actual milling machine.     

一种面向对象的软件设计模式库的设计

成功地利用模式可以有效提高软件的开发效率和设计质量,通用模式具有较强的普适性,结合具体领域特点形成的实例模式具有更强、更具体的指导作用。为了实现一个辅助设计模式复用的CASE工具,对设计模式的几个面向对象的原则进行分析,提出了一种面向对象的分布式软件实例模式库来存储设计模式,并给出相应的类层次库组织结构、分布式的交互管理和基于聚类的多级索引方法及面向对象的嵌套索引方法。依此存储模式以更有效地管理和利用模式。     

UML和设计模式在AMCCS中的综合应用

统一建模语言(Unified Modeling Language,UML)是一种可视化的面向对象的建模语言.设计模式是面向对象建模的一种辅助设计手段,它总结了面向对象设计的宝贵经验,使得在遇到相似场景时可以直接套用,提高复杂系统的设计效率.结合所实施的民航维修成本控制系统(AirCraft Maintenance Costing Control System,AMCCS)的开发工作,提出了使用UML技术进行系统整体规划设计、使用设计模式细化具体组件和部件的对象建模方法,已取得了良好的效果.     

三维游戏引擎的研究与设计

展示了一款基于设计模式的采用UML设计的三维游戏引擎,该引擎使得开发者更加容易的制作3D游戏。借助使用最频繁的一些设计模式和优良的面向对象设计原则来保持从高度抽象的观点进行设计。设计目的是具备通用性、可复用性以及可扩展性的高性能游戏引擎,分析了其架构,介绍了引擎结构的设计思路,并分析了各种模式的使用所带来的效果。     

Software design pattern mining using classification-based techniques

Design patterns are often used in the development of object-oriented software. It offers reusable abstract information that is helpful in solving recurring design problems. Detecting design patterns is beneficial to the comprehension and maintenance of object-oriented software systems. Several pattern detection techniques based on static analysis often encounter problems when detecting design patterns for identical structures of patterns. In this study, we attempt to detect software design patterns by using software metrics and classification-based techniques. Our study is conducted in two phases: creation of metrics-oriented dataset and detection of software design patterns. The datasets are prepared by using software metrics for the learning of classifiers. Then, pattern detection is performed by using classification-based techniques. To evaluate the proposed method, experiments are conducted using three open source software programs, JHotDraw, QuickUML, and JUnit, and the results are analyzed.     

并行主存数据库系统PRISMA／DB

ＰＲＩＳＭＡ／ＤＢ是一并行的主存关系数据库管理系统。其设计思想主要有两个：第一，将整个数据库存入主存从而获得高性能，第二，系统使用一种面向对象的程序设计语言以模块方式实现，使得这种灵活的组织结构适应于功能和性能方面的分析和试验，目前其原型系统已实现，运行在一个具有１００个结点的多处理机上。本文将其设计和实现细节作一初步介绍。     

A multiple case study of design pattern decay, grime, and rot in evolving software systems

Software designs decay as systems, uses, and operational environments evolve. Decay can involve the design patterns used to structure a system. Classes that participate in design pattern realizations accumulate grime—non-pattern-related code. Design pattern realizations can also rot, when changes break the structural or functional integrity of a design pattern. Design pattern rot can prevent a pattern realization from fulfilling its responsibilities, and thus represents a fault. Grime buildup does not break the structural integrity of a pattern but can reduce system testability and adaptability. This research examined the extent to which software designs actually decay, rot, and accumulate grime by studying the aging of design patterns in three successful object-oriented systems. We generated UML models from the three implementations and employed a multiple case study methodology to analyze the evolution of the designs. We found no evidence of design pattern rot in these systems. However, we found considerable evidence of pattern decay due to grime. Dependencies between design pattern components increased without regard for pattern intent, reducing pattern modularity, and decreasing testability and adaptability. The study of decay and grime showed that the grime that builds up around design patterns is mostly due to increases in coupling.     

Object-oriented design: A goal-driven and pattern-based approach

In recent years, the influences of design patterns on software quality have attracted increasing attention in the area of software engineering, as design patterns encapsulate valuable knowledge to resolve design problems, and more importantly to improve the design quality. One of the key challenges in object-oriented design is how to apply appropriate design patterns during the system development. In this paper, design pattern is analyzed from different perspectives to see how it can facilitate design activities, handle non-functional requirement, solve design problems and resolve design conflicts. Based on the analysis, various kinds of applicability of design patterns are explored and integrated with a goal-driven approach to guiding developers to construct the object-oriented design model in a systematic manner. There are three benefits to the proposed approach: making it easy to meet requirements, helping resolve design conflicts, and facilitating improvement of the design quality.     

A tool for design pattern detection and software architecture reconstruction

It is well known that software maintenance and evolution are expensive activities, both in terms of invested time and money. Reverse engineering activities support the obtainment of abstractions and views from a target system that should help the engineers to maintain, evolve and eventually re-engineer it. Two important tasks pursued by reverse engineering are design pattern detection and software architecture reconstruction, whose main objectives are the identification of the design patterns that have been used in the implementation of a system as well as the generation of views placed at different levels of abstractions, which let the practitioners focus on the overall architecture of the system without worrying about the programming details it has been implemented with.In this context we propose an Eclipse plug-in called MARPLE (Metrics and Architecture Reconstruction Plug-in for Eclipse), which supports both the detection of design patterns and software architecture reconstruction activities through the use of basic elements and metrics that are mechanically extracted from the source code. The development of this platform is mainly based on the exploitation of the Eclipse framework and plug-ins as well as of different Java libraries for data access and graph management and visualization. In this paper we focus our attention on the design pattern detection process.     

管理信息系统的面向对象模型设计

本文论述管理信息系统的面向对象式模型设计方法，把设计过程归结构为面向对象分割、面向对象抽象、构造模块和构成系统模型几大步骤。其中，尤其对为了建设理想性能要求的信息系统而如何分析数据，构造模块，作了深入细致的论述。     

三维模型搜索通用支撑平台的设计与实现*

为满足模型搜索研究领域对数据管理、算法配置和算法验证等工具的集成需求,提出一个模型搜索支撑平台框架。利用面向对象技术,构造一个包含应用程序表现层、应用程序工具层、算法逻辑层、数据抽象层、数据访问层和数据层的多层体系结构;基于“一具体类一表”映射策略实现对象型数据与关系型数据的映射;采用策略模式实现了算法组合和替换的动态配置机制。实际应用表明,该平台可为模型搜索研究提供工具支持。     

面向对象数据库技术在电子商务中的应用

面向对象（Object—Oriented,OO）数据库系统是数据库与OO技术相结合的产物,作为一种新型的数据库系统,它不仅拥有基本功能,而且支持面向对象的数据模型。本文结合了电子商务系统,阐述了面向对象的数据库。重点研究了面向对象数据库系统在电子商务中的应用,并对其设计思想、软件架构、对象操作及布置等做了较为深入的介绍和技术探讨。     

SEIS++:一个油气勘探领域软件建造和集成的模式语言

工业化的软件复用从通用类库进化到了面向领域的应用框架和设计模式,与框架相比,设计模式更集中于软件体系结构中重复出现的设计韵律,它主要由可复用的抽象设计结构组成,特定领域内一组相关的设计模式构成了该领域的模式语言,它们可在领域内重复使用以完成某类特定系统的体系结构设计。     

基于CPN模型的REST服务架构标准特征验证方法研究

当前REST服务架构广泛应用于大规模、可扩展的分布式Web系统中,若应用REST服务架构时不遵循其标准特征,则可能导致基于REST服务架构的Web系统出现性能下降、可扩展性低等问题。因此,实现基于REST服务架构的Web系统前,需要对该系统设计是否满足REST服务架构标准特征进行验证,以提升基于REST服务架构的Web系统的研发质量。提出一种基于CPN模型的REST服务架构标准特征验证方法,即对REST服务架构的五个标准特征约束进行CPN建模,并使用模型状态空间执行路径同步匹配的验证方法,以应用系统的CPN模型和标准特征约束的CPN模型为基础,对模型状态空间中的各自执行路径进行同步匹配,若路径可同步执行完毕,则说明该应用系统满足该REST标准特征约束。以基于REST服务架构的课程管理Web系统为例,验证上述方法的可用性和有效性。实验结果表明,本文所提验证方法可以有效确认基于REST服务架构的Web应用系统设计是否符合REST服务架构的标准特征约束,并在不符合标准特征约束时提供直观、可行的执行数据,便于后续完成应用系统设计缺陷定位及修正。     

Generating code for engineering design systems using software patterns

We illustrate here how software engineers developing engineering design systems can introduce patterns into the conceptual modeling techniques that were developed in the database community and integrate them with techniques that are emerging in the object-oriented analysis and engineering design community. The goal is to raise the level of abstraction used to communicate software specifications and to build applications. This will speed the development and improve the quality of engineering design tools. We show by an example how this can be accomplished through an example software pattern from the software engineering discipline (the observer pattern) [12]. We show how patterns can be automatically supported using the general techniques that were developed in the Semantic Objects, Relationships, and Constraints (SORAC) project [20] for the development of tools, for the specification of databases and for building design systems.     

基于LePUS的设计模式CASE工具的设计与实现

设计模式是软件工程界的热点，在面向对象软件设计中扮演着重要角色，自动化支持设计模式非常必要。为此，以LePUS语言为基础，提出了一个支持设计模式的CASE工具原型模型，该工具支持设计模式代码框架的自动生成，更重要的是该工具可以通过加入新的设计模式而得以扩展。此外，详细分析了实现中的源程序内部表示、设计模式实例化、动态模板生成技术等关键技术。