WebML contributor : Baskar P (from MphasiS Software Services) What is WebML? WebML (Web Modeling Language) is a visual notation for designing complex data-intensive Web applications. It provides graphical, yet formal, specifications, embodied in a complete design process, which can be assisted by visual design tools, like WebRatio. WebML in a nutshell: WebML provides graphical, yet formal, specifications, embodied in a complete design process, which can be assisted by visual design tools. The main objectives of the WebML design process are: (a) expressing the structure of a Web application with a high-level description, which can be used for querying, evolution, and maintenance (b) providing multiple views of the same content (c) separating the information content from its composition into pages, navigation, and presentation, which can be defined and evolved independently (d) storing the meta-information collected during the design process within a repository, which can be used during the lifetime of the application for dynamically generating Web pages (e) modelling users and communities explicitly in the repository, to permit the specification of personalization policies and one-to-one applications;
(f) enabling the specification of data manipulation operations for updating the site content or interacting with arbitrary external services. WebML models: Designing a data-intensive Web site amounts to specifying its characteristics in terms of various orthogonal abstractions, each captured by a distinct model. The structure, composition, navigation, and presentation models enable the description of read-only web sites. They can be extended to cope with the specification of content management and integration with external services, through the addition of operations, which can be defined and added to the hypertext model. They are invoked as a side effect of navigation and permit one to specify commonly found interaction patterns as data entry, personal data management, and shopping carts. WebML concepts: Models:- Structure: data organization Derivation: redundant data definition Composition: definition of site pages as set of subpages and elementary publishing units Navigation: definition of links between pages and between units Presentation: positioning of the units in the page and definition of graphical appearance. Site = Structure + Composition + Navigation + Presentation Designing and maintaining Web applications is one of the major challenges for the software industry of the year 2000. Web Modeling Language (WebML), a notation for specifying complex Web sites at the conceptual level. WebML enables the high-level description of a Web site under distinct orthogonal dimensions: its data content (structural model), the pages that compose it (composition model), the topology of links between pages (navigation model), the layout and graphic requirements for page rendering (presentation model), and the customization features for one-to-one content delivery (personalization model). All the concepts of WebML are associated with a graphic notation and a textual XML syntax. WebML specifications are independent of both the client-side language used for delivering the application to users, and of the server-side platform used to bind data to pages, but they can be effectively used to produce a site implementation in a specific technological setting. WebML guarantees a model-driven approach to Web site development, which is a key factor for defining a novel generation of CASE tools for the construction of complex sites, supporting advanced features like multi-device access, personalization, and evolution management. Further References Webml.org: http://www.webml.org/webml/page1.do Why delete messages? Unlimited storage is just a click away. Go to http://help.yahoo.com/l/in/yahoo/mail/yahoomail/tools/tools-08.html To unsubscribe send a message to [EMAIL PROTECTED] with the subject unsubscribe. To change your subscription to digest mode or make any other changes, please visit the list home page at http://accessindia.org.in/mailman/listinfo/accessindia_accessindia.org.in
