基于XML的实时系统构件规约

给出了基于XML描述的实时多任务应用系统图形化设计软件的构件接口语义规约。在基于刻面描述的实时软构件的基础上引入XML Schema技术,全面描述了实时构件的静态属性和接口行为,以方便构件在Web中进行信息交换与处理,方便系统之间的互操作。     

一种基于运行时交互约束的COTS构件集成测试用例生成方法

COTS(Commercial Off-The-Shelf)构件的源代码不可得,而且规约通常缺少交互语义信息,使得集成了COTS的构件软件系统无法采用基于源代码和基于规约的集成测试用例生成方法.提出基于运行时交互约束的COTS构件集成测试用例生成方法.方法在构件软件系统的初始功能测试用例执行过程中,获取COTS构件在系统上下文环境中的运行时接口交互约束信息,建立COTS构件与系统中其它构件的交互约束模型,根据建立的构件交互约束模型生成集成测试用例.当替换、更新集成的COTS构件时,采用生成的集成测试用例验证重新集成的COTS构件与系统其它构件交互的正确性.实现方法的自动化工具原型,并采用真实的系统实例对生成的测试用例的有效性进行了初步评估.     

基于XML的构件化软件集成测试方法研究

分析了当前构件化软件集成测试方法的局限性,利用XML技术特性,使用XML描述构件、构件的交互、构件间交互服从的规约、测试用例及测试序列等,并结合基于规约的测试方法,从而提出一种基于XML的规约驱动的构件化软件集成测试方法。     

面向对象范型体系结构中构件行为相容性研究

软件体系结构(SA)为基于构件的软件开发提供了一种高层次的抽象.如何有效描述体系结构中构件的对外交互行为、验证组装构件间的行为相容及保证整个体系结构行为无死锁是其中较为重要的研究内容.在基于面向对象范型这类重要的软件体系结构中,构件组装通常是通过接口方法调用加以实现.针对这样一类基于软件体系结构的构件组装问题,形式描述与定义了构件及其对外交互协议,分析了服务请求构件与服务提供构件所能展示的不同行为,给出了组装交互的构件在请求/提供接口上协议级行为相容的一组验证规则及相关定理.最后,通过一个电子商务应用实例来说明所提出途径的可用性和针对性.     

基于构件动态演化的行为一致性验证方法

为了保证构件在动态演化中的行为一致性,避免不合法的构件演化,提出一种基于进程代数的构件模型,引入对外主动请求接口和内部连接,形式化描述构件及其对外交互协议,给出相关定理和验证算法。实例证明,该构件模型可以验证动态演化中的接口兼容性、外部交互行为一致性,以及运行时行为完整性。     

基于XML和工作流的构件化软件框架研究

基于XML技术,采用构件化设计方式,搭建了构件组装和运行框架,并研究了基于工作流控制方式的构件动态调度策略.用户可以在构件组装框架下集成应用系统,并实现相应的业务功能.     

一种基于语义描述的Web应用构件自动组装与实现方法

构件组装技术是一种将已有的可复用构件遵循特定的组装方案进行组合的技术,组装的结果是一个粒度更大的构件或者是一个完整的应用系统。然而,现有的技术还难以自动组装那些涉及在线人工交互操作的Web应用构件。针对这个问题,提出一种基于语义描述的Web应用构件自动组装与实现方法。该方法首先提出一种扩展OWL-S的针对Web应用构件及其组装的语义化描述方案。基于该描述,可根据用户的应用需求按照匹配规则从众多构件中筛选出符合需求语义描述的Web应用构件。另外,该方法还提出一种OWL-S到符合BPMN2.0标准的映射方案,用于将描述Web应用构件及其组装方式的OWL-S映射为BPMN2.0文件。j BPM流程引擎可加载并解释执行该BPMN文件,从而实现Web应用构件的自动组装与运行。最后,通过一个旅行规划的实例验证了该方法的可行性和有效性。     

基于通用连接器模型的复合构件的组装

基于构件的软件体系结构(SA)由构件与连接器组成,连接器作为构件间的交互实体在SA中扮演着重要角色。现有的连接器模型只能支持特定软件体系结构风格的组装,该文针对构件组装的核心问题：构件间交互的不匹配,采用复合构件组装的方法,提出一种通用连接器模型用以对不同连接器模型进行描述。给出4种复合构件组装机制及各种机制的组装方式,并对复合构件进行扩展,使其具有动态性,能较方便地实现动态体系结构。     

接口连接式构件组装的一种形式化方法

构件组装是基于构件的软件开发的研究重点之一,能够有效地提高软件开发的效率和质量。以往大部分构件组装技术是在“成功组装路线”的前提条件下实现的,缺乏对构件组装正确性的检验。本文改进了常用的接口连接式构件组装技术,采用形式化方法描述和推导与构件以及构件组装相关的问题,给出了映射算法,实现了从构件组装规约向粘合代码的自动转换,为构件组装形式化分析、组装正确性检验提供了保证。     

基于C/S关系的实时系统构件交互规约

给出了基于构件的实时多任务应用系统图形化设计软件的构件接口定义。为解决基于构件的分布式C/S关系的实时软件构件的重用及装配问题,提出了构件相互交互的文本描述语言语法语义规约,其主要刻画了分布式实时构件之间的交互协议及其实时特性。     

基于模型的云应用动态配置框架

云应用是云计算技术在应用层的一种重要体现形式,通常由分布式异构组件构成,且组件相互依赖,配置参数众多。组件依赖导致配置参数间存在关联,使应用运行时弹性扩展难以确定组件实例的配置顺序并保证关联参数的一致性,导致应用扩展后的系统故障和服务不可用。针对这一问题,提出了一种基于模型的云应用动态自配置方法,实现运行时组件实例配置顺序的自动协调,保障配置参数的一致性,提高应用运行时弹性扩展的可靠性。首先提出一种部署配置模型STM(Service-based Topology Model),该模型采用声明式的方法刻画云应用的部署拓扑结构,并基于服务的方式描述组件信息,实现组件间关联关系的分离,涵盖运维部署、扩展、运行时服务状态的监测。 然后 基于该模型,提出了一个云应用动态自配置协议,其基于服务注册发现机制实现组件间强依赖关系的解耦,保证动态调整应用实例时组件配置变化的一致性,实现组件部署配置的并行化。基于上述方法实现了一个原型系统,通过对分布式应用BookStore-TPCW的部署配置和运行时弹性扩展来验证方法的有效性。     

POEMS: end-to-end performance design of large parallel adaptive computational systems

The POEMS project is creating an environment for end-to-end performance modeling of complex parallel and distributed systems, spanning the domains of application software, runtime and operating system software, and hardware architecture. Toward this end, the POEMS framework supports composition of component models from these different domains into an end-to-end system model. This composition can be specified using a generalized graph model of a parallel system, together with interface specifications that carry information about component behaviors and evaluation methods. The POEMS Specification Language compiler will generate an end-to-end system model automatically from such a specification. The components of the target system may be modeled using different modeling paradigms and at various levels of detail. Therefore, evaluation of a POEMS end-to-end system model may require a variety of evaluation tools including specialized equation solvers, queuing network solvers, and discrete event simulators. A single application representation based on static and dynamic task graphs serves as a common workload representation for all these modeling approaches. Sophisticated parallelizing compiler techniques allow this representation to be generated automatically for a given parallel program. POEMS includes a library of predefined analytical and simulation component models of the different domains and a knowledge base that describes performance properties of widely used algorithms. The paper provides an overview of the POEMS methodology and illustrates several of its key components. The modeling capabilities are demonstrated by predicting the performance of alternative configurations of Sweep3D, a benchmark for evaluating wavefront application technologies and high-performance, parallel architectures.     

COM+: the evolution of component services

COM+ encompasses two areas: a fundamental programming architecture for building software components (first defined by the original COM specification) and an integrated suite of component services replete with an associated runtime environment. For many developers, however, the fundamental COM model is insufficient. In the typical corporation, developers build business components that operate as part of a larger application. Developers expend a great deal of effort to build even the simplest of components. They must also create a robust and secure framework for it and ensure that only clients with the proper authorization can perform certain privileged operations using the component. The problem with the bare-bones component model is that developers are left to implement an enormous amount of functionality that has little to do with the goals of the application itself. To reduce the amount of work required to build a complex distributed application, Microsoft developed the Microsoft Transaction Server (MTS), the first Windows-based implementation of a runtime environment to provide component services. These component services operate within a general set of tools and technologies that, together with COM+, form what Microsoft calls the Distributed Internet Applications (DNA) architecture     

基于Web的电信网管子系统互联关键技术

实现基于TMN的电信综合网管系统具有重要的现实意义,这要求将现有的孤立的TMN子系统互联起来,TMN的标准接口Q3的实现是TMN子系统互联的关键技术之一。文中讨论了利用分布式组件技术扩充Q3接口协议栈以构造类Q3来实现CMIS(CommonManagementInformationService)的管理业务的方法,探讨了Q3接口的实现问题。在开发TMN系统时,以Web作为TMN子系统互联的应用平台,探讨了利用B/S结构实现分布式计算应用的问题,综合利用了Web技术、面向对象技术、分布式组件技术,实现了基于TMN的综合管理系统TIMS。     

An interpreter for LOTOS,a specification language for distributed systems

LOTOS is an executable specification language for distributed systems currently being standardized within ISO as a tool for the formal specification of open systems interconnection protocols and services. It is based on an extended version of Milner's calculus of communicating systems (CCS) and on ACT ONE abstract data type (ADT) formalism. A brief introduction to LOTOS is given, along with a discussion of LOTOS operational semantics, and of the executability of LOTOS specifications. Further, an account of a prototype LOTOS interpreter is given, which includes an interactive system that allows the user to direct the execution of a specification (for example, for testing purposes). The interpreter was implemented in YACC/LEX, C and Prolog. The following topics are discussed: syntax and static semantics analysis; translation from LOTOS external format to internal representation; evaluation of ADT value expressions and extended CCS behaviour expressions. It is shown that the interpreter can be used in a variety of ways: to recognize whether a given sequence of interactions is allowed by the specification; to generate randomly chosen sequences of interactions; in a user-guided generation mode, etc.     

Human exploration and development of space: using XML database Space Wide Web: Space Wide Web by adapters in distributed systems configuration from reusable components

Human exploration and development of space will involve opening the space frontier by exploring, using and enabling the development of space through information technology, while expanding the human experience into the far reaches of space. At that point in time we assert that the current primitive World Wide Web (Web) will be replaced and dramatically expanded into an Interstellar Space Wide Web (SWW). The current state-of-the-art low-orbits communications satellites constellations will be dramatically expanded to higher orbits and to orbits supporting work on other remote human colonies. This will be necessary in order to furnish in a human-friendly way the necessary software and information that will be needed in support of Interstellar Space Wide Information Technologies. Many of the problems encountered in conceiving of, modeling, designing and deploying such a facility will be different from those problems encountered in today’s Web. Future research and development work will be to identify some of these problems and to conceptually model a few of their solutions. In this work we describe research into the development of scalable tools and techniques that reduce the effort associated with component integration, both with respect to network environments and with respect to other components within the application. Our approach is also targeted at increasing the reusability of software components and software architectures. Our research is to investigate current problems in leveraging adapters as a means to configure of large-scale Next Generation distributed systems software from reusable architectures and components. Our approach to solving this problem is through the development of a novel configuration model and network-aware runtime environment called SWWACXML, for Space Wide Web Adapter Configuration eXtensible Markup Language. SWWACXML provides support for cross-layer architectural configuration at both the application level and the level of individual network connections. The language associated with this environment captures component interaction properties and network level quality-of-service (QoS) constraints. Adapters will be generated automatically from SWWACXML specifications. These adapters are part of the SWWACXML runtime system. The runtime system includes facilities for automatic configuration and runtime reconfiguration, as well as efficient management of network connections and QoS options. This facilitates reuse because components are not tied to interactions or environments. Another aspect of this work will focus on development and experimentation with a novel Web-based interaction paradigm that allows client adapters to tailor themselves to servers at runtime. One of the strengths of our approach is that clients do not have to be tied to specific servers at implementation time. Rather, a client’s adapter loads an SWWACXML configuration page from the server. The SWWACXML configuration page defines the appropriate interaction, including management of heterogeneous network QoS options. We believe our approach is amenable to facilitate a style of dynamic reconfiguration, where clients can at runtime change server, communication or interaction protocol. Future researchers and developers will design and implement the SWWACXML system in a distributed test-bed. They will develop performance analysis techniques to judge the success and efficiency of our approach.     

基于反射技术的有性能约束特征的软件集成方法研究

软件集成是一种基于构件技术的软件复用实践．提出了一个基于反射技术，遵循传统CORBA规范、采用中间件技术和特有构件模型(具有性能约束的构件模型PCCM)的解决方案一基于反射技术有性能约束特征的软件集成．其特点是对传统软件集成方法进行扩充，引入反射技术，具体化性能约束的静态描述和集成中间件的性能约束动态机制，建立能够保障单一性能约束、组合性能约束的统一开放式模型．最后给出一个相应案例．     

基于组件程序的模型及动态唤醒

软件重用致力于根据已存组件的构造软件,在应用重用技术进行设计时,所需考虑的一个重要问题是如何唤醒底层子组件的服务,本文首先给出了基于组件设计的模型,然后给出了一种动态唤醍的策略,这种唤醒方式通过动态说明匹配和考察组件的运行时特性来确定目标线件,并较之静肪唤醒提供了更多的的灵活性和扩展性。