Incremental development of UML specifications using operation refinements

In an incremental specification development process, operations are used to model dynamic aspects and can be refined gradually. We propose four kinds of operation refinement in order to control modifications when developing and refactoring UML specifications. Each refinement is described with its properties and illustrated by an example, showing which verifications can be done, using the B formal method.     

OCL-Based Automated Validation Method for UML Specifications

The paper is devoted to the validation of visual software models. The aim of the validation is to verify whether the models match the visual project language, which is a dialect of a standard visual modeling language (UML, SDL, etc.) created with regard to specific features of the particular project on software development. In the paper, an architecture of a validator designed for both interactive and batch modes is suggested. An approach to specifying visual project languages by means of OCL constraints imposed on the UML metamodel with the subsequent automated generation of validators in accordance with the architecture described is suggested. Results of approbation of the validator and the validator generator in the framework of an industry project are presented.     

Automated training-set creation for software architecture traceability problem

Automated trace retrieval methods based on machine-learning algorithms can significantly reduce the cost and effort needed to create and maintain traceability links between requirements, architecture and source code. However, there is always an upfront cost to train such algorithms to detect relevant architectural information for each quality attribute in the code. In practice, training supervised or semi-supervised algorithms requires the expert to collect several files of architectural tactics that implement a quality requirement and train a learning method. Establishing such a training set can take weeks to months to complete. Furthermore, the effectiveness of this approach is largely dependent upon the knowledge of the expert. In this paper, we present three baseline approaches for the creation of training data. These approaches are (i) Manual Expert-Based, (ii) Automated Web-Mining, which generates training sets by automatically mining tactic’s APIs from technical programming websites, and lastly (iii) Automated Big-Data Analysis, which mines ultra-large scale code repositories to generate training sets. We compare the trace-link creation accuracy achieved using each of these three baseline approaches and discuss the costs and benefits associated with them. Additionally, in a separate study, we investigate the impact of training set size on the accuracy of recovering trace links. The results indicate that automated techniques can create a reliable training set for the problem of tracing architectural tactics.     

Automated support for deriving test requirements from UML statecharts

Many statechart-based testing strategies result in specifying a set of paths to be executed through a (flattened) statechart. These techniques can usually be easily automated so that the tester does not have to go through the tedious procedure of deriving paths manually to comply with a coverage criterion. The next step is then to take each test path individually and derive test requirements leading to fully specified test cases. This requires that we determine the system state required for each event/transition that is part of the path to be tested and the input parameter values for all events and actions associated with the transitions. We propose here a methodology towards the automation of this procedure, which is based on a careful normalization and analysis of operation contracts and transition guards written with the Object Constraint Language (OCL). It is illustrated by one case study that exemplifies the steps of our methodology and provides a first evaluation of its applicability. The scope of the testing activity depends on what is modeled by the statechart. If the statechart models the behavior of a single class, then it can be used to support unit testing. If the behavior of a class-cluster, a subsystem or a component is modeled, then we are concerned with integration testing. If the whole system is modeled, then the focus of statechart-based testing is system testing. Lionel C. Briand is on the faculty of the Department of Systems and Computer Engineering, Carleton University, Ottawa, Canada, where he founded and leads the Software Quality Engineering Laboratory (http://www.sce.carleton.ca/Squall/ Squall.htm). He has been granted the Canada Research Chair in Software Quality Engineering and is also a visiting professor at the Simula laboratories, University of Oslo, Norway. Before that he was the software quality engineering department head at the Fraunhofer Institute for Experimental Software Engineering, Germany. Dr. Lionel also worked as a research scientist for the Software Engineering Laboratory, a consortium of the NASA Goddard Space Flight Center, CSC, and the University of Maryland. He has been on the program, steering, or organization committees of many international, IEEE conferences such as ICSE, ICSM, ISSRE, and METRICS. He is the coeditor-in-chief of Empirical Software Engineering (Springer) and is a member of the editorial board of Systems and Software Modeling (Springer). He was on the board of IEEE Transactions on Software Engineering from 2000 to 2004. His research interests include: object-oriented analysis and design, inspections and testing in the context of object-oriented development, quality assurance and control, project planning and risk analysis, and technology evaluation. Lionel received the BSc and MSc degrees in geophysics and computer systems engineering from the University of Paris VI, France. He received the PhD degree in computer science, with high honors, from the University of Paris XI, France. Yvan Labiche received the BSc in Computer System Engineering, from the graduate school of engineering: CUST (Centre Universitaire des Science et Techniques, Clermont-Ferrand), France. He completed a Master of fundamental computer science and production systems in 1995 (Université Blaise Pascal, Clermont Ferrand, France). While doing his Ph.D. in Software Engineering, completed in 2000 at LAAS/CNRS in Toulouse, France, Yvan worked with Aerospatiale Matra Airbus (now EADS Airbus) on the definition of testing strategies for safety-critical, on-board software, developed using object-oriented technologies. In January 2001, Dr. Yvan Labiche joined the Department of Systems and Computer Engineering at Carleton University, as an Assistant Professor. His research interests include: object-oriented analysis and design, software testing in the context of object-oriented development, and technology evaluation. He is a member of the IEEE. Jim (Jingfeng) Cui completed his BSc in Industrial Automation Control, from the School of Information and Engineering, Northeastern University, China. He received a Master of Applied Science (specialization in Software Engineering) in 2004 from the Ottawa-Carleton Institute of Electrical and Computer Engineering, Ottawa, Canada. While in his graduate study, he was awarded the Ontario Graduate Scholarship of Science and Technology. He is now a senior Software Architect in Sunyard System & Engineering Co.Ltd., China. His interest includes Object-Oriented Software Development, Quality Assurance, and Content Management System.     

On using data abstractions for model checking refinements

In this paper we investigate how standard model checkers can be applied to checking refinement relationships between Z specifications. The major obstacle to such a use are the (potentially) infinite data domains in specifications. Consequently, we examine the application of data abstraction techniques for reducing the infinite to a finite state space. Since data abstractions do, however, decrease the amount of information in a specification, refinement can—in general—not be proven on the abstractions anymore, it can only be disproved. The model checker can thus be used to generate counter examples to a refinement relationship. Here, we show how abstract specifications can be systematically constructed (from a given data abstraction) and how a standard model checker (FDR) can be applied to find counter examples in case when refinement is absent. We especially discuss the applicability of the construction method: it constructs abstract specifications which are either upward or downward simulations of the original specifications, and depending on the operations in the specification and the data abstraction chosen, such a construction might succeed or fail. The construction abstracts both the input/output as well as the state.     

A traceability information model for CNC manufacturing

This paper proposes an information model for tracing CNC manufacturing operations. The objective of the model is to assure that traceability data is comprehensive and available for every CNC machined product, independent of the relationship between the subcontractor and the contractor. The prominent feature of the model is a link between CNC report data for a product instance, the CAD design and the CAM data. This link enables users to browse the traceability data and understand the relationships between the manufacturing process, the CAD design and the CAM data. The link is independent of the systems used to build the CAD and CAM data, and allows the users to be sure the manufactured product contains the required characteristics. Then if a product instance fails, this linkage will make possible to analyze the trace data and identify any exceptions or unusual conditions in the manufacturing process.     

Automated transformations from UML behavior models to contracts

In model driven architecture （MDA）, system requirements are first captured by UML （unified mod- eling language） use cases with sequence diagrams to describe their intended use and implemented by classes of objected-oriented languages in the subsequent design stages. It is important that the dynamic behavior specified by the sequence diagrams is in full compliance with the implementation classes. This paper proposes an auto- matic approach and tool support for generating class contracts, which define a precondition and a postcondition for each operation of the class. The former serves as a guard to ensure invocations of the operations respect the semantics introduced by the sequence diagrams, and the latter places the system in a legal state to facilitate the succeeding operation calls. The contracts can be easily mapped to code of an object-oriented language such as Java. Thus, the approach helps to bridge the gap between the requirements and design stages of system development process. We use our model transformation tool to first generate a UML protocol state machine from the sequence diagrams, and then derive the contracts for a controller class. The transformations take into account the concurrency and critical constructs of the respective UML diagrams.     

基于UML的软件测试自动化研究

测试自动化是提高软件测试效率的重要途径。随着UML的广泛应用,基于UML模型的测试逐渐成为面向对象软件测试的研究热点。在总结研究现状的基础上,详细论述了基于UML模型的软件测试用例自动生成、自动执行以及结果自动比较的过程,对其中的主要问题进行了理论分析,并提出了实现方法。     

Verifying data refinements using a model checker

In this paper, we consider how refinements between state-based specifications (e.g., written in Z) can be checked by use of a model checker. Specifically, we are interested in the verification of downward and upward simulations which are the standard approach to verifying refinements in state-based notations. We show how downward and upward simulations can be checked using existing temporal logic model checkers.In particular, we show how the branching time temporal logic CTL can be used to encode the standard simulation conditions. We do this for both a blocking, or guarded, interpretation of operations (often used when specifying reactive systems) as well as the more common non-blocking interpretation of operations used in many state-based specification languages (for modelling sequential systems). The approach is general enough to use with any state-based specification language, and we illustrate how refinements between Z specifications can be checked using the SAL CTL model checker using a small example.     

基于改进灰关联分析的目标威胁评估模型研究

目标威胁度评估是指挥决策的重要环节,也是武器资源有效分配的重要依据。灰关联分析（GRA）在评估决策中应用广泛,但其存在一定的局限性。针对传统GRA的局限性,提出了改进的GRA法——RGRA法,建立了目标威胁评估模型,并给出了应用实例及其性能分析。分析结果表明,RGRA是一种切实有效的目标威胁度评估方法,应用该方法的系统效能比应用传统GRA方法提高约10%。RGRA方法综合考虑了决策者的偏好以及数据在形状和数值上的差异,评估模型数学理论严谨,意义明确,具有良好的实用价值。     

A metrics suite for UML model stability

Software and Systems Modeling - Software metrics have become an essential part of software development because of their importance in estimating cost, effort, and time during the development phase....     

UML状态机模型形式化验证技术研究

系统建模是系统开发经常用到的分析设计方法,如何保证模型的正确性一直是人们关注的话题.为了验证系统设计的模型正确性,进而提高整个系统的质量,提出了一种通过模型检查技术对UML状态机模型进行动态语义验证的方法.对状态机模型进行形式化描述,根据定义的映射规则将图形信息映射成模型检查器可以读取的语言,分析待验证的性质内容,通过使用模型检查器得到验证结果.     

Automated Prototyping of User Interfaces Based on UML Scenarios

User interface (UI) prototyping and scenario engineering have become popular techniques. Yet, the transition from scenario to formal specifications and the generation of UI code is still ill-defined and essentially a manual task, and the two techniques lack integration in the overall requirements engineering process. In this paper, we suggest an approach for requirements engineering that generates a user interface prototype from scenarios and yields a formal specification of the application. Scenarios are acquired in the form of collaboration diagrams as defined by the Unified Modeling Language (UML), and are enriched with user interface (UI) information. These diagrams are automatically transformed into UML Statechart specifications of the UI objects involved. From the set of obtained specifications, a UI prototype is generated that is embedded in a UI builder environment for further refinement. Based on end user feedback, the collaboration diagrams and the UI prototype may be iteratively refined, and the result of the overall process is a specification consisting of the Statechart diagrams of all the objects involved, together with the generated and refined prototype of the UI. The algorithms underlying this process have been implemented and exercised on a number of examples. This research was mainly conducted at University of Montreal, where the first two authors were PhD students and the third author a full-time faculty member. Funding was provided in part by FCAR (Fonds pour la formation des chercheurs et l'aide à la recherche au Québec) and by the SPOOL project organized by CSER (Consortium Software Engineering Research) which is funded by Bell Canada, NSERC (Natural Sciences and Research Council of Canada), and NRC (National Research Council Canada).     

基于UML的信息系统需求分析模型

针对目前常用的需求分析方法存在的弊端,提出了一种基于UML的信息系统需求分析模型,该模型提供了一个基于UML信息系统需求分析框架及其应用过程.实践表明,该模型对信息系统开发具有较好的适应性.     

UML模型检测方法的研究

统一建模语言（UML）是设计和分析软件系统最常用的方法，如何保证UML模型满足某些特性是一个非常重要的问题，而模型检测是一种能够有效提高系统可靠性的自动化技术。研究了使用简单进程元语言解释器（SPIN）对UML模型进行检测的方法。首先对UML模型进行形式化描述，使用层次自动机来描述状态图，然后根据层次自动机的操作语义将状态图和类图的部分信息转化为SPIN的输入语言PROMELA，使用SPIN来验证模型是否满足给定的线性时序逻辑所描述的系统约束，通过LTL公式描述顺序图的方式来验证与状态图之间的一致性问题。项目组基于此方法还开发了一套模型检测工具UMLChecker。     

Automated modeling for structural analysis

The numerical computations required for structural analysis are well defined and easy to automate. If structural analysis is to be automated fully, however, the modeling process, as well as the numerical computations, must be automated. This paper outlines a procedure for the automation of the entire modeling and analysis sequence.Structural analysis is considered as one of several planning, design, and analysis applications to be included in a computerintegrated design system. An essential ingredient of such a system is a central data base that supports all applications. A data base using a hierarchicalcomponent-connection concept is first described. A procedure is then outlined by which a modeler program can extract analysis models from this data base. Whereas the central data base describes the structure in terms of its components and connections, the analysis model is in terms of nodes, elements, substructures, slaving constraints, and so on. The features required in a structural analysis program to analyze the resulting model are also described. This program follows well-established principles, but is substantially different in its arhitecture from conventional analysis programs.A simple frame building is used as an example. However, the procedure is believed to be applicable to structures of a variety of types.     

Automated software size estimation based on function points using UML models

A systematic approach to software size estimation is important for accurate project planning. In this paper, we will propose the unified mapping of UML models into function points. The mapping is formally described to enable the automation of the counting procedure. Three estimation levels are defined that correspond to the different abstraction levels of the software system. The level of abstraction influences an estimate's accuracy. Our research, based on a small data set, proved that accuracy increases with each subsequent abstraction level. Changes to the FPA complexity tables for transactional functions will also be proposed in order to better quantify the characteristics of object-oriented software.     

Automated reasoning on UML conceptual schemas with derived information and queries

ContextIt is critical to ensure the quality of a software system in the initial stages of development, and several approaches have been proposed to ensure that a conceptual schema correctly describes the user’s requirements.ObjectiveThe main goal of this paper is to perform automated reasoning on UML schemas containing arbitrary constraints, derived roles, derived attributes and queries, all of which must be specified by OCL expressions.MethodThe UML/OCL schema is encoded in a first order logic formalisation, and an existing reasoning procedure is used to check whether the schema satisfies a set of desirable properties. Due to the undecidability of reasoning in highly expressive schemas, such as those considered here, we also provide a set of conditions that, if satisfied by the schema, ensure that all properties can be checked in a finite period of time.ResultsThis paper extends our previous work on reasoning on UML conceptual schemas with OCL constraints by considering derived attributes and roles that can participate in the definition of other constraints, queries and derivation rules. Queries formalised in OCL can also be validated to check their satisfiability and to detect possible equivalences between them. We also provide a set of conditions that ensure finite reasoning when they are satisfied by the schema under consideration.ConclusionThis approach improves upon previous work by allowing automated reasoning for more expressive UML/OCL conceptual schemas than those considered so far.     

基于扩展的UML构建Web应用系统的WAMDM模型

Windows DNA形态的Web应用正在变得越来越广泛,越来越复杂,越来越难以控制。给出了一种利用扩展UML构建Web应用的方法模型(WAMDM,Web Application Modeling and Developing Methodology)。应用该方法模型来开发Web应用,不仅可以很好地控制系统的复杂性,使Web应用的开发和维护更容易进行,而且将windows DNA的3层设计以一致的方式完全集成,使整个设计开发过程平滑一致。