1. APPLYING COMPONENT BASED WEB ENGINEERING IN AN INTERNATIONAL ENTERPRISE Philipp Obreiter DCTC Shanghai Jiaotong University P.R. China Guntram Gräf Telecooperation Office (TecO) University Of Karlsruhe Germany

2. Problems of Web Application’s development: –Granularity disparity –Irreversible mapping of models –Short development cycles –Ad-hoc approaches still widely adopted * HTML Implementation Model Design Model Component based Web-Engineering: Motivation ?

3. What is Web-Engineering? –Based on Software Engineering concepts –Applied for the development and evolution of Web Applications –Goal: Cost reduction and quality increase What are the benefits of components? –information hiding –base of reuse Component based Web-Engineering: Introduction

4. Component based Web-Engineering: Definition Production of Web Applications: by composing existing components using a defined process including systematic reuse of –components –domain knowledge

5. WebComposition Process Model: Basic concepts Components as base of reuse & development Artifact management –synchronization of component development –systematic identifaction of reuse opportunities Process –Open: Arbitrary subprocesses & development –Base: Spiral model Risk analysis: Maximization of reuse

6. WebComposition Process Model: Evolution Web Application Evolution bus Application Domain Application Domain Application Domain Application Domain as a whole Component level

7. Artifact management –tackles reuse management –by a component repository Component producer –Provides metadata –Within several models Component consumer –Queries on metadata –Within the appropriate model WebComposition Process Model: Reuse

8. Overall process Development process Analysis Design Realization Reuse Management Analysis Test Reuse process Selection of an existent component WebComposition Process Model: An example

9. Project’s environment Web Application had to be built for the internet & intranet of Siemens Ltd. China State of the art at project start: –No reuse strategies & concepts –Ad-hoc develoopment process –Difficult & error-prone maintenance  Dedicated development process and architecture required

10. Development process: An application of the WCPM Traits: –Component store used in place of a repository –Components built as ActiveX in parallel if orthogonal –Web Application built bottom-up by rapid prototyping –Modeling with UML statecharts for the navigational structure

11. Architecture and patterns: The framework Requirements towards the architecture: –stable & robust to prevent architectural drifts –flexible & extendable to ease evolution –component based to ease reuse  Decomposition –3 layers –6 component stereotypes

12. scripts P A D Business Logic Business Logic Business Logic Database Proxies/Decorators Database Proxies/Decorators Database Proxies/Decorators Markup Language Structures Markup Language Structures Markup Language Structures PBO Factory PAI Control Data Structures Data Structures Data Structures Presentation Application Database Architecture and patterns: The framework

13. Control components –manage user-machine-interaction –encapsulate navigational structure Factory components –dynamically compose pages Structure components –hide destination language (f.e. HTML)  Orthogonality Architecture and patterns: The presentation layer

14. Conclusion: Project results Completion after half the time scheduled Quick realization of user requests Working staff’s skills increased Other projects speeded up through reuse

15. Establish a component repository Create Pages dynamically only if needed Use a platform independent component technology Conclusion: Further work to do

16. Questions? More information: http://www.webengineering.org