Martin Gaedke | Technische Universität Chemnitz (original) (raw)

Papers by Martin Gaedke

In Web application development projects, the specification of the envisioned solution is a timeco... more In Web application development projects, the specification of the envisioned solution is a timeconsuming task suffering from communication problems between the developers and the business. Based on our experiences gained in several real-world projects, we propose an approach combining Domain-Specific Languages and a supporting technical platform. Web application development can thus be performed by composing building blocks and configuring them with DSL programs.

Netnomics

The World Wide Web has become an environment for distributed applications of all kinds. The origi... more The World Wide Web has become an environment for distributed applications of all kinds. The originally intended use of the Web as distributed system for knowledge-interchange seems to disappear, compared to the increasing number of Electronic Commerce Web applications. Organizations offer products and services in the Web, and use the Web as a means to integrate their (heterogeneous) business application systems. Offering Web-based products requires combining services of different application systems, which were build on the coarse-grained Web implementation model. Reusing the respective fine-grained services and application systems respectively integrating these cross-platform application systems increases quality and reduces costs of the new product. However, communication between (legacy) business application systems has to be ensured on an abstract level to realize this scenario. The Web as a global point of sale seems to be very promising but obviously suffers from its heritage-the coarse-grained implementation model. We introduce a generic integration layer that uses an object-oriented approach as well as the WebComposition Markup Language to facilitate the reuse of code and design, and show how inter-application communication can be provided by means of an additional basic integration layer.

Self-Adaptive Web-Applications

Australasian Journal of Information Systems, 2000

The lifecycle of Web-based applications is characterized by frequent changes to content, user int... more The lifecycle of Web-based applications is characterized by frequent changes to content, user interface, and functionality. Updating content, improving the services provided to users, drives further development of a Web-based application. The major goal for the success of a Web-based application becomes therefore its evolution. Though, development and maintenance of Web-based applications suffers from the underlying document-based implementation model. A disciplined evolution of Web-based applications requires the application of software engineering practice for systematic further development and reuse of software artifacts. In this contribution we suggest to adopt the component paradigm to development and evolution of Web-based applications. The approach is based on a dedicated component-technology and component-software architecture. It allows abstracting from many technical aspects related to the Web as an application platform by introducing domain specific markup languages. These languages allow the description of services, which represent domain-components in our Web-component-software approach. Domain experts with limited knowledge of technical details can therefore describe application functionality and the evolution of orthogonal aspects of the application can be de-coupled. The whole approach is based on XML to achieve the necessary standardization and economic efficiency for the use in real world projects.

Lecture Notes in Computer Science, 2000

The Web has become a ubiquitous environment for application delivery. The originally intended ide... more The Web has become a ubiquitous environment for application delivery. The originally intended idea, as a distributed system for knowledgeinterchange, has given way to organizations offering their products and services using the Web as a global point of sale. The centralized delivery-mechanism enables the construction of E-Commerce applications personalized for each user by using behavior analysis. Current technologies suffer from the Web's legacy and use Log file-analysis or collaborative filtering only to adapt the content to users' needs. Motivated by the results of collaborative filtering algorithms, we describe a construction approach based on the abstract concept of services. To support the fine-grained concept we use the component-based WebComposition Markup Language to support reuse and seamless evolution of E-Commerce applications.

Proceedings of the 2000 ACM symposium on Applied computing - Volume 2, 2000

The World Wide Web's anticipated scope as an environment for knowledge exchange has changed drama... more The World Wide Web's anticipated scope as an environment for knowledge exchange has changed dramatically. Without major modifications to its primary mechanisms the Web has turned into a platform for distributed applications. The originally simple and well-defined coarse-grained implementation model of the Web now hinders Web application development. Fine-grained development artifacts, design patterns, and other well-established Software Engineering methods are hard to reuse in the Web after they have found their way into implementation resources. The application of Software Engineering practice to development for the Web, which is also referred to as Web Engineering, and especially the systematic reuse of components for Web-application development at low-costs is a main goal to achieve. This paper presents a systematic approach to code reuse with the WebComposition Repository, which is an essential tool for retrieval and classification of large component sets. The Repository's architecture is crafted to support multiple representation and classification approaches. It facilitates reuse in component-based Web Engineering.

Lecture Notes in Computer Science

The content of many innovative Web sites today often originates from beyond the application. This... more The content of many innovative Web sites today often originates from beyond the application. This paper is concerned with building Web applications that heavily integrate and link content from external sources, like e.g. Web services or RSS feeds. Unlike conventional applications, they are characterized by a very dynamic and distributed information space. In this context, traditional Web Engineering approaches suffer from the fact that they rely too much on a-priori knowledge of existing content structures. We present a support system and a method for building such applications in a very flexible way. Flexibility is achieved by managing links separately from the content in a dedicated Web service and by composing the application from fine-grained, reusable components that realize navigation, presentation, and interaction for the linked content.

Data Warehousing and Web Engineering

Developing application systems that use the World Wide Web (WWW, Web) as an application platform ... more Developing application systems that use the World Wide Web (WWW, Web) as an application platform suffers from the absence of disciplined approaches to develop such Web-applications. Besides, the Web’s implementation model makes it difficult to apply well-known process models to the development and evolution of Web-applications. On the other hand, component-based software development appears as a promising approach that meets essential requirements of developing and evolving highly dynamic Web-applications. With respect to Web-applications, its main objective is to build Web-applications from (standardized) components. Founded on these insights and based on a dedicated component model, we propose an approach to a disciplined specification of components.

From a software-engineering perspective the World Wide Web is a new application platform. The und... more From a software-engineering perspective the World Wide Web is a new application platform. The underlying implementation model of the Web complicates the development and even more the evolution of Web applications. The fact that the Web is a highly dynamic and innovative environment suggests that the advantages of component-based software development can be very useful for the development and evolution of Web applications, but such an approach requires dedicated support. The architecture suggested in this contribution addresses this issue by supporting the component-based development and evolution of Web applications. Furthermore by introducing domain specific markup languages for the description of Web-services a mechanism is introduced that makes it possible to abstract from many technical aspects related to the Web as an application platform. Thus application functionality can be described by domain experts with limited knowledge of technical details and the evolution of orthogonal aspects of the application can be decoupled. The whole approach is based on XML-technology to achieve the necessary flexibility and economic efficiency for the use in real world projects by using widely available standard tools.

The World Wide Web (WWW, Web) has become a new application platform offering most services needed... more The World Wide Web (WWW, Web) has become a new application platform offering most services needed for a distributed operating system. With this, an opportunity is created that allows fusing originally separated business application systems to support new, value-added business applications accessible via the Web. In this paper, we present an approach to facilitate collaboration of business application systems. In particular, we point out how new Web-based business applications are created by fusing services of existing application systems that may reside in heterogeneous environments. Furthermore, we introduce a means to support inter-application communication on a semantic level, thus providing a global information infrastructure for Web-based business applications that supports resource management.

Proceedings of the 32nd Annual Hawaii International Conference on Systems Sciences. 1999. HICSS-32. Abstracts and CD-ROM of Full Papers

The web implementation model is based on a low level technology and does not provide abstractions... more The web implementation model is based on a low level technology and does not provide abstractions for capturing higher level design-concepts, therefor design decisions are difficult to track in an implementation, so that maintenance becomes a difficult and error-prone task. In this paper we introduce the WebComposition system addressing this problem. This system is based on a fine-grained object-oriented web application model. Services are logical units or business processes represented as groups of WebComposition components. The automatic creation for this class of components is possible using service factories, which are modeled on creational design patterns. Service factories enhance the planning for the evolution of the overall structure of large-scale web sites. WebComposition maintains access to all resources throughout the lifecycle for management and maintenance activities. Modifications of the model are made effective in the web by incrementally mapping the model to filebased resources.

Das World Wide Web (Web) ist in einem Wandel vom einem Informationsmedium zu einer Plattform für ... more Das World Wide Web (Web) ist in einem Wandel vom einem Informationsmedium zu einer Plattform für verteilte (betriebliche) Anwendungen begriffen. Mehr und mehr Unternehmen gehen dazu über Waren und Dienstleistungen über das Web anzubieten. Darüber hinaus nutzen sie das Web als Mittel, um ihre oft heterogenen betrieblichen Anwendungssysteme zu föderieren. Das Web wird so gleichermaßen als Vertriebskanal und Integrationsplattform genutzt. Dementsprechend ist auch der Begriff Produkt überladen. So kann mit Produkt einerseits das hergestellte Ergebnis einer Unternehmung gemeint sein, oder andererseits, aus dem Blickwinkel der Softwaretechnik, das Webbasierte Ergebnis der Föderierung von Anwendungssystemen verschiedener Unternehmen. Um ein derartiges Produkt zu erstellen, ist es notwendig, Dienste, die von verschiedenen (betrieblichen) Anwendungssystemen angeboten werden, zu einem neuen, Webbasierten Dienst, dem Produkt, zusammenzustellen. Dazu schlagen wir die Verwendung einer generischen Föderierungsschicht vor und beschreiben deren Realisierung unter Nutzung der WebComposition Markup Language (WCML). Um darüber hinaus eine Kommunikation zwischen den beteiligten Anwendungssystemen zu unterstützen, welche die betriebswirtschaftliche Semantik bewahrt, ergänzen wir die generische Föderierungsschicht um eine statische Föderierungsschicht.

The originally anticipated scope of the World Wide Web (Web, WWW) as a distributed system for kno... more The originally anticipated scope of the World Wide Web (Web, WWW) as a distributed system for knowledge-interchange has changed dramatically. The Web has become an efficient environment for application delivery that is capable of enhancing the style of business processes. Although the possibilities of electronic commerce (ecommerce) look promising, fine-grained design and development of such applications suffers from the legacy of the underlying coarse-grained Web implementation model. The gap between a design model and the Web implementation model leads to an evolutionary development process that is hard to maintain. Beyond that, as the architecture of an ecommerce application matures, more and more knowledge about application domains becomes embodied into code and burdens maintenance or reuse of parts of the application. In this paper, we introduce the object-oriented WebComposition Markup Language (WCML) as basis for a generic framework for e-commerce applications, which improves maintaining of the applications evolution. Characteristic for the proposed framework is the notion of services as subject to runtime configuration and manipulation as well as an XML tuplespace to support data interchange between legacy systems.

The Web has become an efficient environment for application delivery. The originally intended ide... more The Web has become an efficient environment for application delivery. The originally intended idea, as a distributed system for knowledge-interchange, has given way to organizations offering their products and services using the Web as a global point of sale. Although the arising possibilities look promising, the development process remains ad-hoc in real-life Web development. The understanding of Web application development mostly neglects architectural approaches, resulting in Web sites that fail in achieving typical goals like evolvable and maintainable structures of the information space. Beyond that, as the architecture of a Web application matures, more and more knowledge about the domain becomes embodied into code and therefore burdens maintenance and reuse of parts of the application. In this paper, we will propose an architecture and a framework using the notion of services as model entities for Web application development. The object-oriented WebComposition Markup Language, which is an application of the XML, will be presented as basis for a generic evolvable framework for services. Finally, the results of its usage will be described in detail by giving an example of a large-scale transnational Intranet, where the framework is in use.

Developing distributed Web-based solutions is not only a difficult task from the technological pe... more Developing distributed Web-based solutions is not only a difficult task from the technological perspective. Communication problems concerning hypermedia and Web aspects between the developers and the business are an additional major roadblock to a project's success. In order to clarify these communication issues, we report from our experiences gained in a large-scale Enterprise Application Integration project. We address this problem area by applying Domain-Specific Languages and a supporting technical framework. Our overall vision is to enable domain experts to directly contribute to the development effort by autonomously specifying parts of the solution. A set of DSLs and notations derived from our experiences covering central concerns of Web applications is presented: navigation and structuring of application domains, data interaction using Web services, and Web-based process guidance. Web applications can thus be built in an evolutionary manner by composing building blocks whose behavior is configured with DSL programs. Our approach emphasizes conceiving communication with stakeholders and Web application development in a holistic way.

Das WorldWide Web (Web) konnte sich innerhalb kürzester Zeit als Plattform für verteilte Anwendun... more Das WorldWide Web (Web) konnte sich innerhalb kürzester Zeit als Plattform für verteilte Anwendungen etablieren. Zunehmend nutzen mehr und mehr Organisationen dieses Medium, um ihre Produkte und Dienstleistungen anzubieten. Web-Anwendungen für den elektronischen Handel sind nicht nur durch eine Anbindung an betriebliche Anwendungen geprägt, sondern erfordern vielmehr eine adäquate Umsetzung von betrieblichen Abläufen im Web. Das einfache, dokumentenbasierte Implementierungsmodell, das dem Web zugrunde liegt, behindert jedoch den Entwurf und insbesondere die Wartbarkeit und Evolution von Web-Anwendungen. Die Evolution einer Web-Anwendung erfordert den Zugriff auf Entwurfs-und Implementierungsartefakte, um diese ändern oder wiederverwenden zu können. Nach der Abbildung auf das grobgranulare Web-Implementierungsmodell ist dies jedoch nicht mehr möglich. Die Anforderungen, die an betriebliche Web-Anwendungen gestellt werden, können daher ohne einen disziplinierten Ansatz analog zur Softwaretechnik nicht erfüllt werden. In diesem Beitrag wird das objektorientierte WebComposition System als Unterstützung für die komponentenorientierte Entwicklung von Web-Anwendungen vorgestellt. Insbesondere wird gezeigt, wie dadurch eine disziplinierte Wiederverwendung feingranularer betrieblicher Layout-, Interaktions-und Navigationskomponenten umgesetzt werden kann.

Offering Web-based products often requires that services of different application systems can be ... more Offering Web-based products often requires that services of different application systems can be combined to a new product that hides the respective fine-grained services and application systems from the customer-thus federating these application systems. Moreover, communication between (legacy) business application systems federated to "produce" a given product has to be ensured on a semantic level. To support this scenario, we introduce a generic federation layer that uses an object-oriented approach as well as the WebComposition Markup Language to facilitate the reuse of code and design. In addition, we show how a semantic inter-application communication can be provided by means of a second basic federation layer.

The understanding of Web application development mostly neglects approaches to Hypermedia concept... more The understanding of Web application development mostly neglects approaches to Hypermedia concepts and manageable structures of the information space, resulting in Web sites that fail in achieving typical goals that are important for evolving applications. The implementation model of the Web burdens the application of design methodologies like object-orientation due to the document-centric granularity. To overcome this gap a disciplined engineering approach is necessary. In this paper we present a dedicated process model, which enables a software-engineer to map an object-oriented design to the Web implementation model using a component-based implementation technology and a supporting framework.

IEEE Internet Computing, 1999

Computer Networks and ISDN Systems, 1997

Maintenance of web applications is a difficult and error-prone task because many design decisions... more Maintenance of web applications is a difficult and error-prone task because many design decisions are not directly at run time, but rather embedded in file-based resources. In this paper we introduce the WebComposition system addressing this problem. This system is based on a fine-grained object-oriented web application model, and maintains access to it throughout the lifecycle for management and maintenance activities. Modifications of the model are made effective in the web by incrementally mapping the model to file-based resources.