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1.
In object-oriented database systems(OOBSs),the traditional transaction models are no longer suitable because of the difference between the object-oriented data model(OODM)and the conventional data models(e.g.relational data model).In this paper,transction models for advanced database applications are reviewed and their shortcomings are analyzed.Exchangeability of operations is proposed instead of commuativity and recoverability for using more semantics in transaction management.As a result,an object-oriented transaction model(in short,OOTM)is presented.It is not modeled for some special application,but directly based on object-oriented paradigms.A transaction is regarded as an interpretation of a metho.Each transaction(even subtransactions)keeps relative ACID(Atomicity,Consistency,Isolation,Durability)properties,therefore the special problems appearing in OOBSs such as“long transactions”,“visibility of inconsistent database state”can be solved.  相似文献   

2.
首先结合面向对象技术特性,对面向对象软件类级别的CK度量方法和系统级别的MOOD度量方法进行了分析,并就CK度量提出了优化的度量方法OCK。然后结合OCK度量和MOOD度量的优点提出了较优化的面向对象软件复杂性度量方法OSCM。OSCM度量可以有效地弥补CK度量和MOOD度量的不足,优化度量结果。  相似文献   

3.
A product database for a design and manufacturing enterprise serves as a repository for the data needed to manufacture a product. This paper discusses how an object-oriented persistent object manager named ROSE, under development at Rensselaer, has been used in the Rensselaer CIM program to develop a STEP/PDES-compliant product database for its research test bed. In so doing, it provides an overview of the requirements for a product database system in an integrated design and manufacturing facility, and it discusses how the chosen system meets these requirements.  相似文献   

4.
软件测试的目的是发现错误,而不是确认其正确性,是为了增强人们对软件能够按照需求者的期望正确运行的信心,因此需要对软件测试质量进行度量.由于面向对象软件所具有的特性,面向对象软件的测试的度量相对于在过程测试中的测试度量已经不再适应.利用切片和领域的概念,通过多层次的测试度量来对面向对象软件的测试进行评估,该方法能够为改进对面向对象软件系统的测试过程和测试策略提供帮助.  相似文献   

5.
A non-invasive approach for capture and playback (C&P) can be a very useful tool for testing applications endowed of a graphic user interface in local and/or distributed environments, and in general for testing applications without modifying their run-time environment. In the software lifecycle, the phases ofC&P are performed after the application design. Since these are close to the delivery deadline, the time needed for application testing is considered as a high, and frequently unacceptable, cost. In this paper, a new approach for non-invasiveC&P testing techniques is proposed. This is strongly based on the object-oriented paradigm at both hardware and software levels. In particular, a new board for image grabbing and pattern matching, and a new object-oriented language for specifying the tests have been defined. The main goals of this new approach are (i) the reduction of testing time by supporting the reuse of tests (coded by using a specific language) at each level of abstraction, and (ii) the anticipation of the capture-phase of testing with the system design.  相似文献   

6.
软件度量学是软件工程领域的一个重要研究方向。通过软件度量,可以改进软件的体系结构,采用合适的软件开发过程,从而降低软件开发的成本,提高软件开发的效率,保证软件能满足用户的需求,开发出高质量的软件。分析了面向对象软件度量的特点,阐述了常用的面向对象软件度量方法,并在此基础上提出了以切片为中心的度量方法。  相似文献   

7.
A new reusability metric for object-oriented software   总被引:1,自引:0,他引:1  
Software Quality Journal - Software reuse is big business. Managers of software houses know that reuse can bring financial rewards to their company, so long as effective reuse procedures are in...  相似文献   

8.
In this article, an ongoing research project held in the Computer Science department of the University of Vigo is described. Its main objective is to develop an interactive object-oriented environment, serving as a vehicle for learning object-oriented programming. It currently consists of a virtual machine, an assembler, compilers for two high-level programming languages, and an educational visual programming environment. Its main characteristics are (a) the support of prototype-based object orientation, which is a model of object orientation that actually wraps the class-based model; (b) the support for object persistence, which simplifies all input/output issues to the minimum, and (c) the availability of a new visual programming environment is an invaluable help. We the authors think that the combination of all of these possibilities, will lead to an interesting, useful tool that would be recommended for object-oriented teaching. The whole system has been successfully employed in a number of different courses, allowing students to concentrate on objects and their relationships from the very beginning, and thus helping them to achieve a high degree of knowledge about the object-oriented programming paradigm.  相似文献   

9.
面向对象软件测试是面向对象软件开发的一个重要阶段,是保证软件质量、提高软件可靠性的关键,而类测试又是面向对象软件测试的关键。文章针对面向对象程序的特性对软件测试的影响,研究了一种基于状态的类测试方法,从而能够更有效地对面向对象软件进行测试,提高了软件的质量。  相似文献   

10.
An object-oriented model for FMS control   总被引:2,自引:0,他引:2  
The flexible manufacturing system (FMS) is a distributed network of heterogeneous programmable manufacturing machinery, such as assembly lines and numerically controlled machines. Despite these interconnected, programmable hardware elements, the success of building a truly flexible manufacturing system has been limited so far, owing to the lack of flexibility in its control software layer. In integrating heterogeneous machinery, many existing FMS control software systems depend structurally on specific machinery and job-scheduling strategies, and thus it is difficult to incorporate new developments in FMS organization and operational requirements. In searching for an open architecture for the FMS control software system, this paper presents an object-oriented FMS data model. Among others, it represents each physical cluster of related machinery (called a flexible manufacturing cell) as an object. To facilitate the integration of heterogeneous physical cells, such cell objects share a common protocol of interacting with the main control process through inheritance from the abstract cell class. Other related physical and abstract entities in FMS are also modelled as objects, with their similarity and difference captured in inheritance hierarchies. To verify the proposed approach experimentally, a prototype FMS control software system named FREE (FMS Runtime Executive Environment) has been implemented on top of a commercial object-oriented database system.  相似文献   

11.
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.  相似文献   

12.
The object-oriented approach is being used in several areas of computing, including programming, databases, computer-aided design, and office information systems. The paper is a tutorial introduction to object-oriented databases, which is a new application in this field, although object-oriented programming has been under development since the late 1960s. The paper describes the background to object-oriented databases and outlines the rationale for this approach. It concludes with a possible application, in this case a cartographic database, explaining why the object-oriented approach is more appropriate to this application than traditional database approaches, such as the relational approach.  相似文献   

13.
This empirical research was undertaken as part of a multi-method programme of research to investigate unsupported claims made of object-oriented technology. A series of subject-based laboratory experiments, including an internal replication, tested the effect of inheritance depth on the maintainability of object-oriented software. Subjects were timed performing identical maintenance tasks on object-oriented software with a hierarchy of three levels of inheritance depth and equivalent object-based software with no inheritance. This was then replicated with more experienced subjects. In a second experiment of similar design, subjects were timed performing identical maintenance tasks on object-oriented software with a hierarchy of five levels of inheritance depth and the equivalent object-based software.The collected data showed that subjects maintaining object-oriented software with three levels of inheritance depth performed the maintenance tasks significantly quicker than those maintaining equivalent object-based software with no inheritance. In contrast, subjects maintaining the object-oriented software with five levels of inheritance depth took longer, on average, than the subjects maintaining the equivalent object-based software (although statistical significance was not obtained). Subjects' source code solutions and debriefing questionnaires provided some evidence suggesting subjects began to experience difficulties with the deeper inheritance hierarchy.It is not at all obvious that object-oriented software is going to be more maintainable in the long run. These findings are sufficiently important that attempts to verify the results should be made by independent researchers.  相似文献   

14.
侯雪梅  于磊  张兴隆  李志博 《计算机应用》2015,35(10):2990-2994
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。  相似文献   

15.
An object-oriented bill of materials system for dynamic product management   总被引:3,自引:0,他引:3  
In this paper, the bill of materials (BOM) system is defined as the central hub of a general product data management (PDM) system that provides essential data for running a manufacturing system to produce products. Information that is relevant to products and their components is defined in the BOM. The information is critically related to data from product design, manufacturing planning, production management, procurement, inventory control, and accounting within a company. A conventional BOM structure (or product configuration), which manages data only in a stand-alone relational database management style, cannot satisfy the needs requested by all departments within a company. A BOM should relate to and communicate with other domains of the information system. In this research, a newly designed BOM system uses the object-oriented programming (OOP) concept to represent product information. The object-oriented BOM (OOBOM) system can capture and encapsulate data that will simultaneously serve the information needs of various departments. In order to manage product data dynamically, the system provides several interfaces for easy data access and manipulation. The linkage between BOM and its corresponding CAD/CAM system is enabled through the X-window manager: thus an integrated PDM environment is developed. This product management approach improves the consistency and efficiency of product data representation.  相似文献   

16.
介绍了数据仓库技术的概念与内容,研究了运用面向对象技术建立数据仓库系统的关键技术。以某化工企业决策支持系统为背景,给出了基于面向对象技术的数据仓库的设计方案,并对其逻辑设计,前端展现程序设计进行了探讨。  相似文献   

17.
SCKE:Combining Logic- with Object-Oriented Paradigm   总被引:1,自引:1,他引:0       下载免费PDF全文
A new implementation(SCKE-Structured Communication Knowledge Entity)has been proposed towards combining the logic with the object-oriented paradigm of computing.It is intended to explore the advatnages in these two paradigms in a structured,natural and efficient manner for large-scale knowledge processing.The SCKE model supports modularity and protection for the structured development of knowledge systems.It also introduces the concepts that are typical for the object-oriented systems in the logic-oriented paradigm,without losing its advantages as a declarative language.Various inheritance hierarchies are supported in the SCKE model.They provide the semantics basis basis for various knowledge in AI systems.The M-entity/K-entity/Instance inberitance captures the relationship among the control,procedural and factural knowledge in AI systems.And ,the super-entity/entity/instance inheritance shows the concepts of data abstraction in the knowledge of a particular domain.In addition,the SCKE model is not simply supported on top of Prolog like other attempts to integrate the object-into the logic-oriented paradigm.The SCKE model is a tightly coupled model of the logic and the object-oriented paradigm and its interpreter uniformly interprets the logic semantics and the object-oriented semantics.  相似文献   

18.
The term ‘object-oriented database’ has been used to refer to different characteristics and mechanisms supported by semantic databases and (behaviorally) object-oriented ones. While this indicates the current confusion due to the lack of a common model, it also suggests the potential desirability of combining these two kinds of modeling facilities into the same nutshell. This paper summarizes from these two paradigms the features common to both, the features influenced/adopted by each other, and the features which are presented in one paradigm but missing from the other. After a brief analysis and discussion of these features, we conclude this paper by proposing our major theme: a complete object data model should take the union of the facilities offered by these two kinds of models.  相似文献   

19.
DeltaV是一种管理FFCS(Foundation Fieldbus Control System)的软件系统,用面向对象技术开发其仿真支撑环境,建立了流程图组态类库,包括设备类、仪表类、物流类等等,每一类都定义有如类型、种类、方向、位置、颜色、标记等属性,同时定义了对象的建立、标记、移动和缩放等方法,可灵活地增减类库成员和改变属性和方法。  相似文献   

20.
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