Dynamic coupling measurement for object-oriented software

The relationships between coupling and external quality factors of object-oriented software have been studied extensively for the past few years. For example, several studies have identified clear empirical relationships between class-level coupling and class fault-proneness. A common way to define and measure coupling is through structural properties and static code analysis. However, because of polymorphism, dynamic binding, and the common presence of unused ("dead") code in commercial software, the resulting coupling measures are imprecise as they do not perfectly reflect the actual coupling taking place among classes at runtime. For example, when using static analysis to measure coupling, it is difficult and sometimes impossible to determine what actual methods can be invoked from a client class if those methods are overridden in the subclasses of the server classes. Coupling measurement has traditionally been performed using static code analysis, because most of the existing work was done on nonobject oriented code and because dynamic code analysis is more expensive and complex to perform. For modern software systems, however, this focus on static analysis can be problematic because although dynamic binding existed before the advent of object-orientation, its usage has increased significantly in the last decade. We describe how coupling can be defined and precisely measured based on dynamic analysis of systems. We refer to this type of coupling as dynamic coupling. An empirical evaluation of the proposed dynamic coupling measures is reported in which we study the relationship of these measures with the change proneness of classes. Data from maintenance releases of a large Java system are used for this purpose. Preliminary results suggest that some dynamic coupling measures are significant indicators of change proneness and that they complement existing coupling measures based on static analysis.     

Using structural and semantic measures to improve software modularization

Changes during software evolution and poor design decisions often lead to packages that are hard to understand and maintain, because they usually group together classes with unrelated responsibilities. One way to improve such packages is to decompose them into smaller, more cohesive packages. The difficulty lies in the fact that most definitions and interpretations of cohesion are rather vague and the multitude of measures proposed by researchers usually capture only one aspect of cohesion. We propose a new technique for automatic re-modularization of packages, which uses structural and semantic measures to decompose a package into smaller, more cohesive ones. The paper presents the new approach as well as an empirical study, which evaluates the decompositions proposed by the new technique. The results of the evaluation indicate that the decomposed packages have better cohesion without a deterioration of coupling and the re-modularizations proposed by the tool are also meaningful from a functional point of view.     

A Model-Based Approach to Object-Oriented Software Metrics

The need to improve software productivity and software quality has put forward the research on software metrics technology and the development of software metrics tool to support related activities.To support object-oriented software metrics practice efectively,a model-absed approach to object-oriented software metrics is proposed in this paper.This approach guides the metrics users to adopt the quality metrics model to measure the object-oriented software products .The development of the model can be achieved by using a top-down approach.This approach explicitly proposes the conception of absolute normalization computation and relative normalization computation for a metrics model.Moreover,a generic software metrics tool-Jade Bird Object-Oriented Metrics Tool(JBOOMT)is designed to implement this approach.The parser-based approach adopted by the tool makes the information of the source program accurate and complete for measurement.It supports various customizable hierarchical metrics models and provides a flexible user interface for users to manipulate the models.It also supports absolute and relative normalization mechanisms in different situations.     

架构和面向对象技术在PLC软件开发中的应用

为降低开发实时多任务控制系统PLC软件的复杂性、提高软件开发效率和质量,把架构和对象技术引入了PLC软件开发。结合对象技术和控制系统特点,强调了抽象对象的概念,提出了被控对象和控制器对象分离的思想,指出了对象技术的适用范围,设计了PLC控制软件架构的结构模型和控制风格。该模型中单元机器级应用对象技术,在单元机器控制软件内部应用面向任务分析与设计方法,并在一个分布式输送机组的控制软件中实现了该模型。     

Conceptual feature generation for textual information using a conceptual network constructed from Wikipedia

A proper semantic representation of textual information underlies many natural language processing tasks. In this paper, a novel semantic annotator is presented to generate conceptual features for text documents. A comprehensive conceptual network is automatically constructed with the aid of Wikipedia that has been represented as a Markov chain. Furthermore, semantic annotator gets a fragment of natural language text and initiates a random walk to generate conceptual features that represent topical semantic of the input text. The generated conceptual features are applicable to many natural language processing tasks where the input is textual information and the output is a decision based on its context. Consequently, the effectiveness of the generated features is evaluated in the task of document clustering and classification. Empirical results demonstrate that representing text using conceptual features and considering the relations between concepts can significantly improve not only the bag of words representation but also other state‐of‐the‐art approaches.     

Integrating information retrieval, execution and link analysis algorithms to improve feature location in software

Data fusion is the process of integrating multiple sources of information such that their combination yields better results than if the data sources are used individually. This paper applies the idea of data fusion to feature location, the process of identifying the source code that implements specific functionality in software. A data fusion model for feature location is presented which defines new feature location techniques based on combining information from textual, dynamic, and web mining or link analyses algorithms applied to software. A novel contribution of the proposed model is the use of advanced web mining algorithms to analyze execution information during feature location. The results of an extensive evaluation on three Java systems indicate that the new feature location techniques based on web mining improve the effectiveness of existing approaches by as much as 87%.     

基于硬件特征信息嵌入认证的软件保护

为了既方便软件开发、降低成本,又便于软件保护、维护权益人的利益,研究了软件保护的常用技术和方法,结合软件工程的具体实践,提出了基于硬件特征信息嵌入认证的软件保护方法.该方法的主要特点是利用用户计算机系统的硬件特征信息,采用特征信息嵌入法,通过对当前计算机特征信息与已认证特征信息表中的信息进行比对,实现基于认证的软件保护;同时使用有效的加密算法,进一步提高软件保护强度.实验结果表明,该方法设计简单、成本低、通用性强、保护强度高,是软件保护的有效方法.     

A LISP-based object-oriented approach to structural analysis

An approach to structural analysis is presented in which object-oriented data structures make it possible to arrange computational tasks in a unique fashion. A general matrix-free solution algorithm for use with arbitrary assemblages of linearly connected objects is presented, followed by an overview of a prototype structural analysis program built entirely on such an object-oriented data structure. The principal result is due to the flexibility inherent in this type of data structure, which makes it possible to analyze structural models incrementally as they are developed. Although certainly useful in traditional contexts, the parallel nature of the scheme could be particularly powerful in a multiprocessor environment.     

Empirical assessment of the impact of structural properties on the changeability of object-oriented software

The changeability of software can be viewed as the quality of being capable of change, which among others implies that the task of changing the software requires little effort. It is hypothesized that structural properties of the software affect changeability, in which case measures of such properties can be used as changeability indicators.Ways in which structural properties of the software can be measured are described and empirically validated based on data collected from an industrial Java development project. The measures are validated by using them as candidate variables in a multivariate regression model of the actual effort required to make modifications to the evolving software system.The results suggest that some measures that combine existing structural attribute measures with a weighting factor based on the relative proportion of change in each class can explain a large amount of the variation in change effort. This constitutes initial, empirical evidence that the proposed measures are valid changeability indicators. Consequently, they may help designers to identify and correct design problems during the development and maintenance of object-oriented software.     

面向对象软件测试及度量的研究

软件测试方法和度量是提高和保证软件质量的关键,文中介绍了一种认识面向对象软件集成测试和试想量的方法（URI）,以及一种继承树深度（DIT）的度量标准,从这一测试方法显示继承的过多使用将增加软件测试的复杂性,论文最后介绍了有待进一步研究的问题。     

Measurement of language-supported reuse in object-oriented and object-based software

A major benefit of object-oriented software development is the support for reuse provided by object-oriented and object-based languages. Yet, measures and measurement tools that quantify such language-supported reuse have been lacking. Comprehensive reuse measures, particularly for reuse with modifications, are necessary to evaluate the status of reuse in an organization and to monitor improvements. We develop a set of measurable reuse attributes appropriate to object-oriented and object-based systems and a suite of measures that quantify these attributes. One of our major objectives is to measure reuse in software written in the object-based language Ada. A set of suitable primitive reuse measures are expressed in Ada Reuse Tables. These tables support the flexible use of primitive measures in programs with nested packages and subprograms, and Ada generic packages. We designed and implemented a prototype Ada Reuse Measurement Analyzer (ARMA) to generate measurement values from Ada programs. ARMA produces a reuse data representation and a corresponding forest representation of an Ada system that contain the information necessary to produce the primitive measures. Developers can use the representations to produce customized reports to satisfy a wide range of measurement goals. We use ARMA to measure primitive reuse attributes for a set of industrial Ada software. We also show that ARMA can be used to generate a set of component access and package visibility measures.     

面向对象的方法在软件设计中的应用研究

文中结合一个大型税收管理信息系统的开发，详细介绍了一种面向对象的系统设计方法的实施步骤、组织关系和分析评价，侧和理实用性。     

面向对象软件的依赖性分析与回归测试

针对面向对象软件中类之间复杂的依赖性问题,通过分析UML类图中类之间的各种静态关系,提出一个基于UML类图的依赖性分析模型。为了实现自动化分析,引入了类依赖关系图的概念,并提出一个基于UML类图导出的XMI文件的类依赖关系图生成算法。根据这个模型,通过分析一个类或依赖关系的改变对其他类产生的影响,提出测试路径查找算法,并利用此算法得到需要进行回归测试的类集与测试序列。     

面向对象软件系统的一种度量方法及其应用

在面向对象系统分析和设计过程中，类的设计质量直接关系到软件系统质量。首先对类之间的关系进行了分析、说明和定义，并分为横向关系和纵向关系，给出了横向关系和纵向关系度量与质量评价，并在此基础上给出了改善类设计质量的方法。     

Assessing the maintainability of software product line feature models using structural metrics

A software product line is a unified representation of a set of conceptually similar software systems that share many common features and satisfy the requirements of a particular domain. Within the context of software product lines, feature models are tree-like structures that are widely used for modeling and representing the inherent commonality and variability of software product lines. Given the fact that many different software systems can be spawned from a single software product line, it can be anticipated that a low-quality design can ripple through to many spawned software systems. Therefore, the need for early indicators of external quality attributes is recognized in order to avoid the implications of defective and low-quality design during the late stages of production. In this paper, we propose a set of structural metrics for software product line feature models and theoretically validate them using valid measurement-theoretic principles. Further, we investigate through controlled experimentation whether these structural metrics can be good predictors (early indicators) of the three main subcharacteristics of maintainability: analyzability, changeability, and understandability. More specifically, a four-step analysis is conducted: (1) investigating whether feature model structural metrics are correlated with feature model maintainability through the employment of classical statistical correlation techniques; (2) understanding how well each of the structural metrics can serve as discriminatory references for maintainability; (3) identifying the sufficient set of structural metrics for evaluating each of the subcharacteristics of maintainability; and (4) evaluating how well different prediction models based on the proposed structural metrics can perform in indicating the maintainability of a feature model. Results obtained from the controlled experiment support the idea that useful prediction models can be built for the purpose of evaluating feature model maintainability using early structural metrics. Some of the structural metrics show significant correlation with the subjective perception of the subjects about the maintainability of the feature models.     

Using clustering and dynamic mutual information for topic feature selection

A good feature selection method should take into account both category information and high‐frequency information to select useful features that can effectively display the information of a target. Because basic mutual information (BMI) prefers low‐frequency features and ignores high‐frequency features, clustering mutual information is proposed, which is based on clustering and makes effective high‐frequency features become unique, better integrating category information and useful high‐frequency information. Time is an important factor in topic detection and tracking (TDT). In order to improve the performance of TDT, time difference is integrated into clustering mutual information to dynamically adjust the mutual information, and then another algorithm called the dynamic clustering mutual information (DCMI) is given. In order to obtain the optimal subsets to display topics information, an objective function is proposed, which is based on the idea that a good feature subset should have the smallest distance within‐class and the largest distance across‐class. Experiments on TDT4 corpora using this objective function are performed; then, comparing the performances of BMI, DCMI, and the only existed topic feature selection algorithm Incremental Term Frequency‐Inverted Document Frequency (ITF‐IDF), these performance information will be displayed by four figures. Computation time of DCMI is previously lower than BMI and ITF‐IDF. The optimal normalized‐detection performance (C_det)_norm of DCMI is decreased by 0.3044 and 0.0970 compared with those of BMI and ITF‐IDF, respectively.     

Algorithmic support for model transformation in object-oriented software development

Current methods for object-oriented software development provide notation for the specification of models, yet do not sufficiently relate the different model types to each other, nor do they provide support for transformations from one model type to another. This makes transformations a manual activity, which increases the risk of inconsistencies among models and may lead to a loss of information. We have developed and implemented an algorithm supporting one of the transitions from analysis to design, the transformation of scenario models into behavior models. This algorithm supports the Unified Modelling Language (UML), mapping the UML's collaboration diagrams into state transition diagrams. We believe that CASE tools implementing such algorithms will be highly beneficial in object-oriented software development. In this paper, we provide an overview of our algorithm and discuss all its major steps. The algorithm is detailed in semi-formal English and illustrated with a number of examples. Furthermore, the algorithm is assessed from different perspectives, such as scope and role in the overall development process, issues in the design of the algorithm, complexity, implementation and experimentation, and related work. Copyright © 2001 John Wiley & Sons, Ltd.     

面向对象软件测试的蜕变关系构造方法

针对面向对象软件类级测试中方法序列调用时的Oracle问题,提出了一种基于代数规格的面向对象蜕变关系构造方法,并根据此方法进行蜕变测试。首先基于代数规格给出面向对象测试中蜕变关系的构造准则,然后根据构造准则对GFT(Generating a Finite number of Test cases)算法中范式构造蜕变关系方法进行改进,最后通过一个整数栈类对提出的蜕变关系构造准则进行了验证测试,并与GFT算法中范式构造蜕变关系方法进行了对比,结果表明在相似的变异检测率下,改进后的方法使得构造的蜕变关系冗余度降低了66%,验证了改进的蜕变关系构造方法有更低的蜕变关系冗余度,提高了软件测试效率。     

Methods for controlling the authenticity of textual information transfer on the basis of statistical and structural redundancy

In this paper,the problem of increasing information transfer authenticity is formulated.And to reach a decision,the control methods and algorithms based on the use of statistical and structural information redundancy are presented.It is assumed that the controllable information is submitted as the text element images and it contains redundancy,caused by statistical relations and non-uniformity probability distribution of the transmitted data.The use of statistical redundancy allows to develop the adaptive rules of the authenticity control which take into account non-stationarity properties of image data while transferring the information.The structural redundancy peculiar to the container of image in a data transfer package is used for developing new rules to control the information authenticity on the basis of pattern recognition mechanisms.The techniques offered in this work are used to estimate the authenticity in structure of data transfer packages.The results of comparative analysis for developed methods and algorithms show that their parameters of efficiency are increased by criterion of probability of undetected mistakes,labour input and cost of realization.     

Using a tree model in textual analysis

The purpose of this paper is to show the utility of the application of a non-ultrametric tree-model to textual data. The first part introduces a basic topological property of the tree and the notion of neighbourhood, which reflects the structure of the tree. The second part emphasizes through illustration examples the adequacy of this model for representing different varieties of textual data.Luong received a Doctoral ès Science at the University of Paris. He is lecturer in Computer Science at the University of Nice. His main research interests are in data analysis, mathematical models for social science and humanities.