Engineering Web-Based Systems with UML Assets

Software development is a product of evolution. It builds on the experiences of the individual and the community, continually refining every aspect of process. Web centric architectures are no different. Their ever-increasing levels of functionality and complexity are evident in the latest generations of web applications. In this paper we discuss some standards that enable teams to build, communicate and apply their experiences in the art of web application software development. These standards appropriate various levels of abstraction, and bring the focus of web application development back to the team. Combining UML representation of web-based systems with techniques for packaging these solutions for reuse can positively impact development timelines and efficiencies.     

软件复用在消防远程监控系统中的应用

软件复用有利于提高软件开发的生产效率,降低软件开发的成本,软件构件和领域工程是实现软件复用的核心技术。本文以消防远程监控系统为例,详细阐述了领域分析、领域体系结构设计等过程,并介绍了可复用构件实现方法。     

A model-driven approach to develop high performance web applications

The evolution of web technologies in the last few years has contributed to the improvement of web applications, and with the appearance of AJAX and Web 2.0 technology, a new breed of applications for the Internet has emerged: widgets, gadgets and mashups are some examples of this trend. However, as web applications become more and more complex, development costs are increasing in an exponential rate, and we believe that considering a software engineering methodology in the development process of this type of applications, contributes to the solution of this problem. In order to solve this question, this paper proposes a model-driven architecture to support web application development from the design to the implementation model. With this aim, the following tasks have been performed: first a new profile extends UML with new concepts extracted from the web domain, then a new framework supports web application development by composing heterogeneous web elements, and finally, a transformation model generates web applications from the UML extension proposed. The main contribution of this work is a cost and complexity reduction due to the incorporation of a model-driven architecture into the web application development process, but other advantages that can be mentioned are a high performance degree achieved by a prefetching cache mechanism, and a high reusability, since web elements can be reused in different web applications.     

面向对象与软件复用技术研究

软件复用是软件开发中避免重复劳动的一种行之有效的解决方案,好的复用技术可以节约开发成本,缩短开发时间,带来高可靠、高性能、高质量和高效率的软件新系统。面向对象技术是一个非常实用且强有力的软件开发方法,并阐述了软件复用在面向对象方法中的应用。     

面向对象与软件复用技术研究

软件复用是软件开发中避免重复劳动的一种行之有效的解决方案 ,好的复用技术可以节约开发成本 ,缩短开发时间 ,带来高可靠、高性能、高质量和高效率的软件新系统。面向对象技术是一个非常实用且强有力的软件开发方法 ,可为软件复用提供基本的技术支持。介绍了软件复用的基本概念和关键技术 ,并阐述了软件复用在面向对象方法中的应用。     

基于J2EE的Web应用系统的性能优化方法研究

应用软件的性能优化是计算机应用的重要问题。良好的性能是企业应用系统的重要质量指标之一。本文以一个基于J2EE的ERP系统的开发实践为背景,从减少网络通信量,使用缓存技术和优化数据访问这三个方面讨论了基于J2EE的Web应用系统的性能优化的一系列方法,并提供了这些方法的实际应用效果的测试数据。     

面向方面技术在Web服务安全组合中的应用研究

Web服务作为一种通过网络集成分布式异构应用的技术,它提供了一种松散耦合的软件开发模式,实现了粗粒度的软件重用。随着Web服务技术的深入应用,Web服务组合的概念应运而生,它通过将功能相对单一的多个Web服务按照一定粒度进行组合,可提供更为强大的服务功能。由于来自异构环境的不同Web服务实体间安全需求、安全能力、可信任程度间的差异,使得对Web服务组合安全性的研究成为了关注的重点。简述了Web服务组合的主要实现方式,指出了Web服务组合实现中面临的主要安全问题,重点分析了目前面向方面技术在Web服务安全组合实现中的应用,讨论了其实现上的不足及未来的研究动向。     

Feature‐based approach to object‐oriented engineering of applications for reuse

Object‐oriented technology is gaining popularity among software engineers with the goal of building reusable and adaptable software. Unfortunately, however, most methods introduced so far are not domain‐oriented and do not address the issue of reuse directly. For these methods, software reuse is not the primary goal; it is only a by‐product. The feature‐oriented reuse method, FORM, is extended in this paper for improving the object‐oriented engineering of applications for reuse. FORM concentrates on analyzing and modeling commonalities and differences in the applications of a given domain in terms of capability, operating environment, domain technology, and implementation technique features. These features are used to systematically derive objects that are tied to the features, and to develop reusable and adaptable domain architectures. We found that FORM facilitates analysis of variability (and commonality) of software before engineering and implementation start, and with this understanding, adaptability and reusability can be built into software. Feature modeling has been found to be an effective method for identifying and modeling reusable objects. Copyright © 2000 John Wiley & Sons, Ltd.     

一种基于构件软件仿真的成本估算方法

随着面向对象和软件复用技术的发展。产生了一种新的基于构件的软件开发方法,被广大软件开发人员普遍看好,发展很快。为了解决基于构件的软件开发成本估算的问题。结合构件的复用成本公式。在分析基于构件的软件开发方法特点的基础上提出了一种基于构件仿真的软件成本估算方法。利用分解法的思想,以传统开发方法的成本为基础,将基于构件的软件开发过程分成若干阶段,分别估算各阶段的成本,最终得到估算结果,为基于构件的软件开发成本估算提供了一个较好方法。最后给出了对该估算方法的评价,指出了今后研究的重点。     

Through Personalized Web Service Composition Specification: From BPEL to C-BPEL

Over the last few years, Web services technologies offered a new and successful way for interoperability among web applications. A Web service is a software system designed in a way that other software components and humans can discover and invoke to satisfy different needs. The vision of WS as a software component allows to combine several WS, providing a global value-added WS, called composite WS.Although there are several researches in web services composition, more effort should be focused on its personalization, particularly regarding how well the composition results correspond to what the user really wants. Accordingly, we present in this paper an approach that may contribute to the personalization of web services composition specification. Our approach is a context-based proposal that makes services composition specification more efficient by taking into account both user context, needs, and preferences and web services context, and by integrating them to the composition process. In addition, to permit the reuse of specifications, we enhance BPEL by developing a specification language based on context to be used in composition that we called C-BPEL.     

Leveraging bandwidth improvements to web servers through enhanced network interfaces

Markets nowadays demand applications that require high communication throughputs to reach their adequate levels of performance. Although the bandwidth of the network links has increased allowing multiple gigabits per second, taking advantage of these links accounts for a high communication overhead, and thus a lot of processor cycles are used for communication tasks, diminishing the processor cycles that remain available for the application. In this paper, we evaluate the performance in web applications of a network interface that as it is distributed among the processors currently available in the node takes advantage of both the hardware (multiprocessor nodes and multicore architectures, as well as programmable network interface cards) and software elements present in the system, thus improving not only the effective communication throughputs and latencies, but also the capacity of the nodes to satisfy the requirements of the applications. Here, the usefulness of this distributed network interface to improve the performance of either static or dynamic web servers is shown. The ubiquity and the different computation/communication rates that can be found in web applications make the analysis of web servers interesting, as it could provide relevant conclusions about the efficiency of the different approaches to the design of high-performance network interfaces.     

Graph-based traceability: a comprehensive approach

In recent years, traceability has been globally accepted as being a key success factor of software development projects. However, the multitude of different, poorly integrated taxonomies, approaches and technologies impedes the application of traceability techniques in practice. This paper presents a comprehensive view on traceability, pertaining to the whole software development process. Based on the state of the art, the field is structured according to six specific activities related to traceability as follows: definition, recording, identification, maintenance, retrieval, and utilization. Using graph technology, a comprehensive and seamless approach for supporting these activities is derived, combining them in one single conceptual framework. This approach supports the definition of metamodels for traceability information, recording of traceability information in graph-based repositories, identification and maintenance of traceability relationships using transformations, as well as retrieval and utilization of traceability information using a graph query language. The approach presented here is applied in the context of the ReDSeeDS project (Requirements Driven Software Development System) that aims at requirements-based software reuse. ReDSeeDS makes use of traceability information to determine potentially reusable architectures, design, or code artifacts based on a given set of reusable requirements. The project provides case studies from different domains for the validation of the approach.     

集群政务协同业务平台架构及关键技术研究

集群政务协同平台包括六大系统。论述了该平台的应用架构和技术架构,阐述了其主要关键技术:多个政务应用的规模集成和协同应用、业务模型驱动的SOA架构通用开发平台、统一资源管理、Web服务安全增强。运行实践表明,平台能够最大限度地整合利用省(市)级政务平台的软硬件资源和政务业务资源,使农村区县基于省(市)级平台构建各自的政务平台,从而实现全省(市)政务平台的城乡统筹建设和维护,提高政务管理和协同办公的效率。     

Modeling presentation layers of web applications for testing

Web software applications have become complex, sophisticated programs that are based on novel computing technologies. Their most essential characteristic is that they represent a different kind of software deployment—most of the software is never delivered to customers’ computers, but remains on servers, allowing customers to run the software across the web. Although powerful, this deployment model brings new challenges to developers and testers. Checking static HTML links is no longer sufficient; web applications must be evaluated as complex software products. This paper focuses on three aspects of web applications that are unique to this type of deployment: (1) an extremely loose form of coupling that features distributed integration, (2) the ability that users have to directly change the potential flow of execution, and (3) the dynamic creation of HTML forms. Taken together, these aspects allow the potential control flow to vary with each execution, thus the possible control flows cannot be determined statically, prohibiting several standard analysis techniques that are fundamental to many software engineering activities. This paper presents a new way to model web applications, based on software couplings that are new to web applications, dynamic flow of control, distributed integration, and partial dynamic web application development. This model is based on the notion of atomic sections, which allow analysis tools to build the analog of a control flow graph for web applications. The atomic section model has numerous applications in web applications; this paper applies the model to the problem of testing web applications.     

Hibernate对Struts框架的扩展研究

引入MVC框架,确定了MVC在Web开发的应用模式,研究了符合MVC标准的Struts框架工作流程及其应用的优势和不足.结合持久化工具Hibernate的功能特点和Struts框架的优势,利用框图描述的方法对Struts框架进行扩展,提出了扩展后的Web开发多层软件体系结构应用模型.扩展后的Struts框架,使Web开发的层次更加清晰,降低了各层之间的耦合,提高了代码的复用性,可使Web开发的效率大幅度提高.     

Requirements model driven adaption and evolution of Internetware

Today’s software systems need to support complex business operations and processes.The development of the web-based software systems has been pushing up the limits of traditional software engineering methodologies and technologies as they are required to be used and updated almost real-time,so that users can interact and share the same applications over the internet as needed.These applications have to adapt quickly to the diversified and dynamic changing requirements in the physical,technological,economical and social environments.As a consequence,we are expecting a major paradigm shift in software engineering to reflect such changes in computing environment in order to better address the fundamental needs of organisations in this new era.Existing software technologies,such as model driven development,business process engineering,online(re-)configuration,composition and adaptation of managerial functionalities are being repurposed to reduce the time taken for software development by reusing software codes.The ability to dynamically combine contents from numerous web sites and local resources,and the ability to instantly publish services worldwide have opened up entirely new possibilities for software development.In retrospect to the ten years applied research on Internetware,we have witnessed such a paradigm shift,which brings about many changes to the developmental experience of conventional web applications.Several related technologies,such as cloud computing,service computing,cyber-physical systems and social computing,have converged to address this emerging issue with emphasis on different aspects.In this paper,we first outline the requirements that the Internetware software paradigm should meet to excel at web application adaptation;we then propose a requirement model driven method for adaptive and evolutionary applications;and we report our experiences and case studies of applying it to an enterprise information system.Our goal is to provide high-level guidelines to researchers and practitioners to meet the challenges of building adaptive industrial-strength applications with the spectrum of processes,techniques and facilities provided within the Internetware paradigm.     

面向服务架构应用技术研究

采用面向服务架构有效地降低软件开发的复杂性,提高软件的复用程度,缩短软件开发周期。但不少开发人员对于Web服务、构件等面向服务架构的相关概念和理论还不甚清楚。论文总结了目前主要的面向服务架构的应用技术,介绍了相关技术细节。     

Development nature matters: An empirical study of code clones in JavaScript applications

Code cloning is one of the active research areas in the software engineering community. Specifically, researchers have conducted numerous empirical studies on code cloning and reported that 7 % to 23 % of the code in a typical software system has been cloned. However, there was less awareness of code clones in dynamically-typed languages and most studies are limited to statically-typed languages such as Java, C, and C++. In addition, most previous studies did not consider different application domains such as standalone projects or web applications. As a result, very little is known about clones in dynamically-typed languages, such as JavaScript, in different application domains. In this paper, we report a large-scale clone detection experiment in a dynamically-typed programming language, JavaScript, for different application domains: web pages and standalone projects. Our experimental results showed that unlike JavaScript standalone projects, JavaScript web applications have 95 % of inter-file clones and 91–97 % of widely scattered clones. We observed that web application developers created clones intentionally and such clones may not be as risky as claimed in previous studies. Understanding the risks of cloning in web applications requires further studies, as cloning may be due to either good or bad intentions. Also, we identified unique development practices such as including browser-dependent or device-specific code in code clones of JavaScript web applications. This indicates that features of programming languages and technologies affect how developers duplicate code.     

用Struts和Hibernate构筑Web应用开发策略

当今越来越多的Web应用是基于MVC设计模式的.此种设计模式提高了应用系统的可维护性、可扩展性和组件的可复用性.Apache开源组织提供的Struts框架充分体现了MVC架构.Hibernate实际上是一个用对象编程思维来操纵数据库的解决方案.提出了一种基于Struts和Hibernate架构的Web应用开发策略.MVC架构中,模型、视图和控制器3个部分中的模型部分（数据持久层）用Hibernate实现,视图和控制器的实现依托于Struts框架.这种策略真正实现了层间的松散耦合.