As well as in traditional software engineering, reuse is a key factor for the efficient and efficacious construction and evolution of complex Web applications. Efficaciously integrated in the development process and supported by an appropriate framework, reuse significantly increases development speed, application quality and, by enabling rapid prototyping, improves stakeholder communications. Although reuse aspects in traditional software engineering have been thoroughly investigated, their successful adoption to the Web Engineering domain still remains nontrivial leaving room for dedicated Web-specific solutions. Beyond that, current consolidation activities in the Web Engineering community underline the significance of a unifying solution. To this end, we present a comprehensive ontology-based Web Engineering reuse approach that establishes a common basis for cross-methodology reuse strategies and emphasizes stakeholder collaboration. To unfold the full potential of reuse, it incorporates both planned and spontaneous reuse strategies. We point out the approach’s extensibility and applicability for cross-methodological Web Engineering and demonstrate how it considerably accelerates development speed and improves stakeholder communications.

Complex dialogs with comprehensive underlying data models are gaining increasing importance in todaypsilas Web applications. This in turn accelerates the need for highly dynamic dialogs offering guidance to the users and reducing cognitive overload. Beyond that, requirements from the fields of Web accessibility, platform-independence and Web service integration arise. Considering the resulting complexity, a systematic engineering approach becomes important. Besides addressing the specific characteristics of these dialogs, key success factors from a communication perspective like strong user involvement and clear business objectives must be taken into account. To this end, we present an evolutionary, extensible approach for the model-driven construction of advanced dialogs which is based on a Domain-specific Language (DSL). We introduce a modeling notation based on Petri net constructs and XForms as well as a supporting Web-based editor, both focusing on simplicity and fostering communications. The technical framework allows for quick prototyping and flexible changes. In conclusion, complex, device-independent dialogs with rich behavior and appearance can be constructed and evolved with intense stakeholder collaboration.

To cope with the increased complexity of todaypsilas Web-based systems, approaches facilitating operations, maintenance and evolution of heterogeneous and distributed systems landscapes are vital. In particular, due to the complex interdependencies between their distributed system parts, assuring that services are delivered at a high level of quality is challenging. To this end, we present the integrated information map (i2map) as an aspect-oriented approach. It considers these interdependencies as first-class citizens and provides sophisticated services addressing the lifecycle support of distributed systems. We exemplarily demonstrate the approachpsilas potential in the context of ontology-based evaluation of service level agreements in a highly interrelated system landscape.

Complex dialogs with comprehensive underlying data models are gaining increasing importance in today's Web applications. This in turn accelerates the need for highly dynamic dialogs offering guidance to the users and thus reducing cognitive overload. Beyond that, requirements from the fields of aesthetics, Web accessibility, platform-independence, and Web service integration arise. To this end, we present an evolutionary, extensible approach for the model-driven construction of advanced dialogs. It is based on a Domain-specific Language (DSL) focusing on simplicity and fostering collaboration with stakeholders.

Establishing efficient and intensive stakeholder collaboration is a key factor in Web application development projects. Therefore, the form of collaboration needs to be shifted from simple conversation to valuable contribution, i.e. empowering stakeholders to directly contribute to the development effort. To achieve this, we introduce an approach combining Domain-specific Languages and an underlying technical platform.

Strong user involvement and clear business objectives, both relying on efficient communication between the developers and the business, are key factors for a project's success. Domain-Specific Languages (DSLs) being simple, highly-focused and tailored to a clear problem domain are a promising alternative to heavy-weight modeling approaches in the field of Web Engineering. Thus, they enable stakeholders to validate, modify and even develop parts of a distributed Web-based solution.