Generation of Asynchronous Component Adapters

Utilizing services of legacy and third party COTS components has become vital for the timely development and evolution of software systems. Component interfaces typically have to be adapted before they can be re-used in a system context. This paper presents an approach to generating component adapters. The approach focuses on mapping multiple events, and their associated parameters, generated from a source component to multiple calls in the target component. The novelty of our mechanism is that it allows developers to generate asynchronous as well as synchronous adapters. As a result we can generate adapters for components with incompatible event structure. A prototype called Asynchronous Component Adapter (ACA) was developed which demonstrates the idea with Java Beans, but the methodology can be applied to any component-based system that supports introspection like Microsoft .NET assemblies.     

基于面向方面技术的服务安全组合故障分析

服务组合作为实现服务增值的一种有效方法,业已广泛使用于各种应用.安全问题是与Web服务密切相关且对于服务组合的可信性具有重要作用.然而目前还缺乏对服务安全组合进行有效描述和分析的方法.提出一种基于面向方面的形式化服务安全组合建模及其分析方法.重点讨论了服务的授权、执行的可追踪、数据保护及故障处理,并利用面向方面规范基本模块的行为、描述它们相互关系的手段,编织机制将这些模块动态地集成为一个完整的服务组合模型.基于此,Petri网的操作语义及相关理论分析服务组合的安全性及故障处理能力,给出服务组合的正确性准则,并证明了其有效性.具体实例及仿真结果表明,该方法能有效地简化系统建模,有助于提高服务组合的设计质量.     

Online reconfiguration of component-based applications in PacoSuite

In this paper, we present an original approach for enabling online reconfiguration of component-based applications. This research fits into our component composition methodology PacoSuite, that makes use of explicit connectors between components, called composition patterns. Both components and composition patterns are documented by making use of a special kind of MSC. We propose an algorithm to check whether a new component can fulfill the role of an old component in a given composition pattern, without the need to revalidate the entire composition all over again. To enable online reconfiguration, we extend the documentation of a component with a new primitive that specifies when a component reaches a safe state. This approach enables to swap a component at run-time, while maintaining a consistent application.     

程序挖掘中的构件组装技术

随着基于构件的程序挖掘思想的提出,在这一概念下的构件组装技术已成为研究重点。文章研究了Internet计算环境的构件特点,在分析构件不匹配和程序挖掘的组装特性的基础上,提出了一种基于分解一适配一综合的DASC组装模型。     

基于软件体系结构的构件组装工具ABC-Tool

软件朝着越来越复杂和庞大的趋势发展,因此对更有效的软件开发技术的需求十分迫切,近年来,软件体系结构、构件技术和软件复用技术等开始在软件开发中发挥重要作用,成为软件工程领域研究的热点,在基于构件复用的开发方法中,构件组装技术是关键,而且一直以来也是难点所在,ABC(architecture-based component composition)是一种基于软件体系结构、面向构件的软件开发方法,介绍了为ABC方法提供有效支持的工具ABC-Tool,ABC-Tool以软件体系结构为设计蓝图,以构件为基本开发单元,在不修改构件源代码的前提下,通过可视化的图形建模方式,从体系结构的高层设计逐层映射到底层实现,将可运行或可部署的构件组装为最终的可正确运行的系统。     

构件组合的集成测试

模型检验是一种自动化验证技术,其应用主要的困难在于状态空间爆炸问题.针对构件组合形成的状态空间爆炸问题,结合构件抽象组合原理及反例引导的抽象精化框架,提出了一种测试用例自动生成的方法.根据某个待集成构件抽象已集成的其他构件,并通过组合各个抽象构件生成抽象组合模型.利用模型检验工具对组合模型进行集成测试,生成抽象测试用例,再通过精化得到原模型对应的具体测试用例.实验结果表明该方法减小了状态空间,在一定程度上减缓了状态空间爆炸的问题.     

面向安全性需求的构件组装

构件组装技术无法充分考虑安全苛求软件的安全性需求,可能引发软件的失效。该文在保证安全苛求软件的基本构件满足功能性需求的同时,提出采用加入时间字约束的方法来确保构件组装后的结果达到安全性需求,使系统按照严格的时序进行状态的变迁,有效避免了故障的发生。     

基于构件库及构件组合的软件重用

介绍了一种具有动态组合特性的构件Ｐａｄ，详细说明了它如何规范重用单元的接口以及相互间可传递的消息，并进一步介绍了构件Ｐａｄ的组合规划消息传递协议，还简村介绍了一种在面向对象数据库的基础上实现构件库的方法，最后，介绍了已开发成功的一个构件重用支撑环境的原型。     

基于消息的构件组合运算与构件演化

根据构件能够接收和发送的消息，扩展了构件接口定义框架，给出了基于消息的构件组合模型，定义了构件的执行路径，对四种组合运算进行了形式化描述，提出并证明了六则构件演化运算．给出了一个实例：把一个没有显示语义的层次系统模型简化为语义明确的树形组合模型，并给出了模型的代数表达式和简化算法．     

构件组装技术在虚拟实验室中的应用研究

基于构件的软件复用技术是实现软件工程化开发和工业化生产的重要途径,其中构件的集成组装是关键。目前虽然提出了许多构件组装理论,但如何在特定领域根据实际要求实施基于构件组装的软件开发过程仍是值得进一步研究的课题。本文针对计算机硬件类虚拟实验室芯片设备复杂多样、难于开发的问题,在深入分析芯片工作原理与结构特征的基础上,提出一种基于数据驱动的构件组装方法。该方法通过充分重用已有芯片构件以可视化组装的方式开发新芯片构件及建模实验,从而有效提高了开发效率同时软件具有很好的易维护性和可扩展性。     

基于软件体系结构的可复用构件的组装

近年来,软件体系结构、构件技术和软件复用等技术开始在软件开发中发挥重要的作用,成为软件工程领域研究的焦点。在基于构件复用的构件方法中,构件组装技术是关键。本文首先阐述并比较了目前国内外几种典型的体系结构,分析给出了它们对构件组装的影响,然后给出基于体系结构的构件组装方法以及ABC—Tool工具在构件组装方面的功能和实现。     

An Invasive Composition System for Local-to-Global Transformations

Transformation systems are particularly well suited to implement modular rules, transforming one language feature of the source language into a single or a composition of language features of the target language. However, in practice, transformation rules must be written which take one language feature and transform them into several language features belonging to various locations in the output program. The implementation of these so-called local-to-global transformations with rewrite rules is very complex and tightly coupled which imposes severe constraints on maintenance and evolvability. The four main coupling problems of the current-day implementations are presented and we indicate how these can be eliminated and reduced by our extension of the rewrite rule system. Furthermore we show how complex invasive compositions can be solved by abstract, reusable algorithms and mechanisms, rendering the implementation of local-to-global transformations into a semi-automatic process.     

基于XML的具有性能约束构件的组装技术

采用在软总线TAO(The ACE ORB)上利用XML文档中所包含的语义化的抽象数据类型对构件对象进行操作,从而实现语义化的性能约束构件组装。建构的XML模式描述了构件组装相关的构件接口、交互及配置规约,并通过接口显式地表达构件对环境的依赖,使得能在一个分布式的网络环境里,将多个处于不同节点、提供紧密相关服务的构件在运行时动态地组装成功能系统。在给出的示例中,实现了将三个分布在不同节点的性能约束构件通过它们接口的交互及配置,实现在运行时开放的松散式组装。最后给出了下一步研究工作的重点及方向。     

Improving the Interoperability in the Digital Home Through the Automatic Generation of Software Adapters from a SysML Model

This paper addresses the motion planning problem of nonholonomic robotic systems. The system’s kinematics are described by a driftless control system with output. It is assumed that the control functions are represented in a parametric form, as truncated orthogonal series. A new motion planning algorithm is proposed based on the solution of a Lagrange-type optimisation problem stated in the linear approximation of the parametrised system. Performance of the algorithm is illustrated by numeric computations for a motion planning problem of the rolling ball.     

基于C2架构的EJB构件组装

在基于构件软件工程（CBSE）开发方法中,构件使用者利用现有构件集成应用系统,因此,如何组装构件一直是人们研究的热点。在分析C2构架和EJB构件标准的基础上,提出了基于C2架构进行EJB构件组装的方法和步骤,并通过实例分析了这种方法的合理性和可重用性。     

基于C2风格的COM构件组装

随着基于构件的软件工程(CBSE)的快速发展,开发人员已经被分成构件生产者和使用者两个群体。不同的构件标准正在被提出和制定,构件的使用正在变得越来越方便。因此,使用工具来组装构件已经成为可能。文章介绍了C2构架和COM标准的特性,并且针对组装过程中一些亟待解决的问题,提出了观点和想法。     

Aspect-oriented interaction in multi-organisational web-based systems

Separation of concerns has been presented as a promising tool to tackle the design of complex systems in which cross-cutting properties that do not fit into the scope of a class must be satisfied. Unfortunately, current proposals assume that objects interact by means of object-oriented method calls, which implies that they embed interactions with others into their functional code. This makes them dependent on this interaction model, and makes it difficult to reuse them in a context in which another interaction model is more suited, e.g., tuple spaces, multiparty meetings, ports, and so forth. In this paper, we show that functionality can be described separately from the interaction model used, which helps enhance reusability of functional code and coordination patterns. Our proposal is innovative in that it is the first that achieves a clear separation between functionality and interaction in an aspect-oriented manner. In order to show that it is feasible, we adapted the multiparty interaction model to the context of multiorganisational web-based systems and developed a class framework to build business objects whose performance rates comparably to handmade implementations; the development time, however, decreases significantly.     

工作流驱动、面向服务的构件组装平台

通过分析基于构件组装的网构软件开发流程,设计了一种工作流驱动、面向服务的构件组装平台CCP-I,该平台在工作流引擎的支持下,可以实现服务构件的动态装配以及构件和Web表单间的松耦合。最后,介绍了基于开源项目的CCP-I平台的实现方案。该平台能够为网构软件支撑平台的研究提供参考和借鉴。     

实时构件合成的语义研究

实时构件合成是实时应用系统中软件合成的基础,是实现软件复用思想的软件生产活动,其语义研究从实时构件的反射式语义模型、实时构件合成的适配性验证和合成构件的语义规约机制三个方面展开,规约为实时构件合成中的分析理论。