An Introduction to XML Rahman Mokhtar a'r'mokhtarlivjm'ac'uk

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An Introduction to XMLRahman Mokhtar
(a.r.mokhtar_at_livjm.ac.uk)

• What is data?, what is information?, what is
  knowledge?
• How do we represent information?
• About markups
• procedural
• generic coding
• generalised
• SGML
• HTML
• XML

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Who would benefit from XML?
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Example Applications?
XML extensible structure (i.e.
independent of presentation) validation
ltprincess countryUKgt Diana lt/princessgt
ltphysics photokoolgt Einstein lt!CDATAE
mc2gt lt/physicsgt
ltprice currencyUK scaleMgt 1 lt/pricegt
Multi-purpose (Multimedia) Publishing
Information storage, sorting, retrieval.
Agent A
Agent B
Business A
Business B
E-commerce Intelligent Agents digital
negotiations transactions
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XML Document and DTD
Well-formedness (against XML syntax) Validation
(against DTD) Parser
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XML Processing Examples of Companion Standards

• XML Document/DTD/Parser
• DOM (access to document objects)
• Script/Programming (manipulation of objects)
• XSL (render ready transformation)
• Browser/Display Application
• (renderer)

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XML Syntax
DTD Syntax

• Elements nesting
• Attributes
• XML document
• Comments
• Unicode
• CDATA
• Namespace
• Processing Instructions

• Elements declaration
• Content model
• Attribute declaration
• Entities
• - general/parameter
• - internal/external
• - parsed/unparsed
• Notations

gt Parser sees meaningless element names gt
Parser differentiates parent-child structure gt
Application provides semantics
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Rendering via XSL Transformation

• XML Stylesheet Language, XSL
• an XML application
• (provides presentation semantics)
• template-driven model
• data-driven model
• sorting and conditional
• transformation
• XSL element names
• (transformation functions)