design and implementation of component-based adaptive web presentations zoltán fiala, michael hinz...

Design and Implementation of Component-based

Adaptive Web Presentations

Zoltán Fiala, Michael HinzTechnische Universität Dresden

Geert-Jan Houben, Flavius FrasincarTechnische Universiteit Eindhoven

{zoltan.fiala, mh5}@inf.tu-dresden.de{g.j.houben, f.frasincar}@tue.nl

SAC 2004 WTA, March 14-17 2004, Nicosia

SAC2004 WTA, March 14-17 2004, Nicosia Zoltán Fiala 2/13

Structure

Motivation A Component-based Document Format Hera-based Development Implementation


Motivation

Today‘s WWW– Personalized ubiquitous medium → Delivery of adapted information needed

– Conventional document formats hardly applicable for this challenge

– Complex authoring process AMACONT project [1]

– Component-based Development of Adaptive Web Presentations

– Composing Web applications from reusable, adaptable document components

Hera project [2]– Structured design methodology for adaptive Web applications

– Model driven specification framework based on RDF(S) Here: Putting it all together

– Combining Hera’s modeling power with a flexible AMACONT implementation

– Extending Hera with AMACONT’s versatile presentation layer

– Automatic transformation from Hera specs. to AMACONT components


A Component-based Document Format

Based on different abstraction levels


Describing Adaptive Behavior

<AmaDocumentComponent name="TVProgram"> <MetaInformation> ... … … </MetaInformation> <Variants> <Variant name="Adult_Program"> ... </Variant> <Variant name="Child_Program"> ... </Variant> </Variants> </AmaDocumentComponent>

<AdaptiveProperties> <If> <Expr operator=”greaterThan”> <UserParam>UserAge</UserParam> <Const>18</Const> </Expr> <Then res="Adult_Program"/> <Else res="Child_Program"/> </If> <AdaptiveProperties>


„Layout Managers“ BorderLayout BoxLayout OverlayLayout GridLayout

Transformers for– xHTML– cHTML– WML

Describing Adaptive Layout

Box-Layout

<LayoutProperties> <alay:LayoutManager> <alay:BoxLayout orientation="yAxis">

<alay:ComponentRef ratio="30%">PictureObject1

</alay:ComponentRef> <alay:ComponentRef ratio="70%">

TextObject1 </alay:ComponentRef> </alay:BoxLayout> </alay:LayoutManager></LayoutProperties>


Hera-based Development

Hypermedia Design Models– Identify Crucial phases of Web development– Specify hypermedia applications in an appropriate level of

abstraction– Already significant research on design and process models

» Aspects of adaptation: Hera [2], OOHDM [3], UWE [4] Idea

– Adoption of existing methods for component-based adaptive Web applications

– Focus: Model driven Hera methodology [2] Benefits

– Automatic translation of Hera schemas to a component-based AMACONT implementation

– Versatile implementation (presentation) layer for Hera framework


Conceptual Design

Conceptual Model (CM)– Represents the application domain

by concepts and concept attributes– Typed concept attributes

(Integer, String, Image, Audio, etc.)– Based on RDFS

Component Development– Creation/retrieval of media instances representing concept

attributes– Encapsulating media instances to components

» Additional metadata, MPEG7 descriptors– Providing alternative media instances with different quality


Application Design

Application Model– Logical, structural and

navigational aspects– Grouping concept attributes

to Slices– Slice: meaningful presentation

unit of some media items

Adaptation Design– Targeting different adaptation aspects in the AM

» Adjusting the coarse navigational structure» Population of slices with media items» Dynamic Adaptation

– Assigning appearance conditions to slice references


Application Design Realization with AMACONT components

– Analogies between Hera slices and components:

» Meaningful presentation units bearing some semantic role» Both top-level slices and top-level document components

correspond to pages to be shown on the user’s display» Contain adaptation issues

Straightforward mapping process– Concept attributes → Media Components– Slices containing attributes from a single concept → Single

Document Components– Slices containing concept attributes and subslices from

different concepts → Composite Document Components » Same (recursive) mapping process for each aggregated subslice


Presentation Design

Presentation Model (PM)– Bridges the logical level

and the actual implementation

– Defines how and where the identified subslices should be displayed

– PD: Presentation Diagram– Idea: Adoption of Layout

Manager Concept


Document Generation


Prototype: Component-based WIS


Conclusion and Future Work Conclusion

– Construction of adaptive Web presentations from components– Combination of the model-based Hera design methodology and

AMACONT’s document formats– Automatic transformation from a high-level specification to a

component-based implementation

Future Work– Dynamic coupling of AMACONT and Hera – Support for presentating data being computed at run-time– Specification, acquirement and evaluation of user interactions– Realizing dynamic adptation in the joint system


Literature

[1] Fiala, Z., Hinz, M., Meissner, K., Wehner, F.: A Component-based Approach for Adaptive, Dynamic Web Documents. Journal of Web Engineering, September 2003

[2] F. Frasincar, G. J. Houben, and R. Vdovjak. Engineering Semantic Web information Systems in Hera. Journal of Web Engineering, September 2003

[3] D. Schwabe, G. Rossi, R. Guimaraes. Designing personalized web applications. WWW10, Hong Kong, 2001

[4] Koch, N., Kraus, A., Hennicker, R.: The authoring process of the UML-based web engineering approach. First International Workshop on Web-Oriented Software Technology. (2001)