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CEAL Preconference Workshop: XML

Wooseob JeongAssistant Professor

School of Information StudiesUniversity of Wisconsin – Milwaukee

March 2, 2004 San Diego, CA

Sponsored by School of Information Studies, University of Wisconsin – Milwaukee

University of California – San Diego Library

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Why XML?

Simply because it’s already everywhere. MS Office XHTML - WYSIWYG PDF RDF - Dublin Core, RSS MARC in XML E-books

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What is XML?

Extensible Markup Language XML is a concept, not an application.

Meta Language Linguistics for individual languages XHTML is an application of XML.

Brief history of XML SGML – HTML Not enough … why?

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Learning XML

No technical experience needed. Even no HTML experience is welcome. HTML vs. XHTML (different families) Again, XML is a concept.

Good starts on XML http://www.infomotions.com

/musings/getting-started/

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XML is simple but very strict. You can make your own mark up set as you like wi

th minimal requirement. Every tag should be paired. Tags should be in a hierarchy.

However, once you establish the set, you have to follow it. It’s the law! No exception. Otherwise, your document won’t be displayed at all. “Well-formedness” – minimum requirement DTD (Document Type Definition)

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Philosophy of XML Separation of presentation information from its co

ntent. No decorating information allowed in contents. Presentation should be rendered by methods outside th

e document, currently either CSS or XSLT CSS has been used in HTML as well as in XML.

Ex) http://www.uwm.edu/~dhedberg/MENU.xml XSLT is more powerful.

Ex) http://web.utk.edu/~rgilmou1/xml4lita/ More Examples

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Markup information Presentational Markup: Describe Appearance

<blockquote>1234 N. Oakland Ave.Milwaukee, WI 53201</blockquote>

Semantic Markup: Indicates Meaning<address><street>1234 N. Oakland Ave.</street><city>Milwaukee</city><state>WI</state><zip>53201</zip></address>

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Your First XML Document

Using NotePad, please follow the instruction at http://supervoca.com/xml/first.htm

The result should look like http://supervoca.com/xml/first.xml

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Restaurant Menu Exercise

Well-formedness CSS (Cascading Style Sheet)

Simple but not flexible XSLT (Extensible Stylesheet Language Tran

sformations) It is an xml document itself. Complex but really powerful

Online Exercises

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Menu CSS Exercise

Use NotePad and type yourself, please! Watch out “save as” option. Modify “menu.xml” with your favorite foods,

adding CSS info. Modify “menu.css” with your prefences. Comprehensive CSS reference

http://www.w3schools.com/css/default.asp

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Menu XSLT Exercise Modify “menu2.xml” by adding XSLT info. Modify “menu2.xsl” with your preference. It is like a limited programming language.

Selective displays with the same data. Examples

You may use HTML tags freely, but every attribute’s value should be quoted.

Watch out typos!

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Unicode in XML Unicode is the default character set in XML. What’s Unicode?

http://unicode.org/ Why is it so important? Where is ASCII? Multilingual vs. Multiscript

WordPad or MS Word should be used for Unicode documents. Save as “Unicode Text”

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“united.xml”<?xml version="1.0"?><?xml-stylesheet type="text/css" href="united.css"?>

<united><English>Eradicate extreme poverty and hunger</English>

<Chinese> 消灭极端贫穷和饥饿 </Chinese>

<French>Réduire l'extrême pauvreté et la faim</French>

<Russian>Ликвидация крайней нищеты и голода</Russian></united>

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“united.css”

English {display: block; color=red}French {display: block; color=blue}Chinse {display: block; color=green}Russian {display: block; color=purple}

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More Unicode Exercise Multilingual/multiscript sources

United Nations International Bible Society

Since an XSLT file is an XML document, you can use any languages or any scripts in your XSLT.

Only Windows 2000 or XP supports Unicode fully. CSS – “bible.xml” XSLT – “biblecjk.xml”

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SMIL Exercise (1)

Synchronized Multimedia Integration Language

Still an XML application! Multiple media are played together.

Example: Closed Captioning. RealText Exercise

Based on Real Player setting

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SMIL Exercise (2)

Locate an audio source. Ex) Voice of America at http://voanews.com

Locate its transcript. Modify “example.smil” file according to your

information. Modify “example.rt” file with your transcript. It can be a “Karaoke” application.

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SMIL Exercise (3) Online Exercise http://supervocab.com/xml Locate any CJK real audio file on the web, and cop

y the URL to the form. Ex) http://homepage.third-wave.com/didreat/kor/real.h

tm Type the script in CJK. Choose a character set and a font.

SMIL in Real Audio does still support local character sets only.

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Document Type Definition

What is DTD? The master plan dictates all the rules for

elements, attributes, and entities. You may make your own DTD, but once

you make it, you should follow the rule. No exception!

Why is DTD important? Data Exchange

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Elements, Attributes, and Entities

Elements Building blocks of markup (tags)

Attributes Qualifying Elements (properties)

Entities Referencing External Content and Saving

Typing Ex) special characters

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DTDs XHTML

TEI (Text Encoding Initiative)

EAD (Encoded Archival Description)

RDF (Resource Description Framework) Dublin Core; RSS

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Validation To be a same type of document, it should be valid

for its DTD.

<!DOCTYPE TEI.2 PUBLIC "-//TEI//DTD TEI Lite XML ver. 1.1//EN" "http://www.tei-c.org/Lite/DTD/teixlite.dtd">

Online validation tool

Well-formedness vs. Validation

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TEI Letter Transcript Exercise The purpose of this exercise is to make a valid TEI

document transcribing a letter. Use a remote TEI DTD

TEIXLite DTD <!DOCTYPE TEI.2 PUBLIC "-//TEI//DTD TEI Lite XML ver.

1.1//EN" "http://www.tei-c.org/Lite/DTD/teixlite.dtd"> Modify “letter.xml” and “letter.css” with your text an

d preference. Do a validation test, please.

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Dublin Core Most Frequent Example in RDF http://dublincore.org/

<?xml version="1.0"?> <!DOCTYPE rdf:RDF PUBLIC "-//DUBLIN CORE//DCMES DTD 2002/07/31//EN" "http://dublincore.org/documents/2002/07/31/dcmes-xml/dcmes-xml-dtd.dtd"> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/"> <rdf:Description rdf:about="http://www.ilrt.bristol.ac.uk/people/cmdjb/"> <dc:title>Dave Beckett's Home Page</dc:title> <dc:creator>Dave Beckett</dc:creator> <dc:publisher>ILRT, University of Bristol</dc:publisher> <dc:date>2002-07-31</dc:date> </rdf:Description> </rdf:RDF>

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RSS (RDF Site Summary)

“Rich Site Summary” More practical and active example in

RDF http://supervocab.com/rss RSS feeds are so many on the web.

http://mtgear.net/index.rdf http://homepage.mac.com/cyberdog_to_go/

iblog/B1549800066/rss.xml http://blog.isism.net/b2rdf.php

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Other important parts in XML (1)

XSL XSL Transformations XSL Formatting Objects

Ex) PDF

URI (Uniform Resource Identifiers) URL (Uniform Resource Locator) ISBN/ISSN

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Other important parts in XML (2) XLINK

More than what HTML links do Ex) inbound link information, behavior of links

(when, how to activate) XPointer

More than what HTML anchors do XPointers refer to particular parts of or location

s in XML documents. Ex) linking to the third sentence of the sevente

enth paragraph in a document

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Other important parts in XML (3)

Namespace An XML namespace is a collection of

names, identified by a URI reference Problem: same element names Ex) title in HTML and title of a book

Schema Alternative to DTD Data type

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Popular E-book Formats Adobe: basically PDF Microsoft Palm Free E-book Projects

http://etext.lib.virginia.edu/ebooks/ebooklist.html

http://www.sois.uwm.edu/xml/ Authoring tools

Universal CJK support cannot be found yet.

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Conclusion XML is a concept.

There are many XML applications. XML should separate its presentation

information from its contents. XML’s default character set is Unicode. XML should be “well-formed” at least. DTD/Schema is very important for

data/information interchange.