Thesis full text (PDF) - Politecnico di Milano

4. Implementation Experience
The concepts presented so far have been implemented in the context of the WebML 2 design
approach [3]. While other implementation approaches could have been followed, the one based
on WebML seemed to be the more convenient and productive. Indeed, other existing UML
C.A.S.E. tools would have been less effective, since they could have helped in producing the
Java code of the components by providing only a set of interfaces and / or stub classes, while all
the coding of the business logics and of the front end Web application would have been manual.
Vice versa, thanks to the WebML model and associated design tools, the components can be
quickly designed and integrated in the visual design of the Web application, whose code can then
be automatically generated. The conceptual components specified in Section 3 have been
implemented once and for all as WebML primitives, which can be reused in the design. A set of
WebML modeling and code generation facilities take care of the Web page implementation of
the method invocations, and of the parameters between components.
4.1 WebML and WebRatio background
This Subsection summarizes the basic concepts of WebML and WebRatio that are needed for
understanding the extensions that have been devised in this work. WebML is a Domain Specific
Model for Web application design and development. It allows specifying the conceptual
modeling of Web application hypertexts (site views) built on top of a content model of the
application data. A site view is a graph of pages. Pages consist of connected units, representing
at a conceptual level the publishing primitives that extract content from the database: a unit
displays instances of an entity, possibly restricted by a selector. Units are related to each other
through hypertextual links, representing navigational paths and carrying data from a unit to
another. WebML allows specifying also operations updating the underlying data or performing
other actions.
2 http://www.webml.com
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