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XML-Based Course Websites
Michael Wollowski
Computer Science and Software Engineering Department
Rose-Hulman Institute of Technology
Introduction: Background
My interest is in search enginesXML promises the development of powerful search enginesPlaced CSSE course descriptions into XMLWrote a search engine for themRealized that editors are easyHave to rely on other people to provide contents
Introduction: Benefits of XML
Separation of form and contentsCommon information can be placed into separate filesWebpages of the same kind are rendered in the same way
Introduction: XML in comparison
Benefits of courseware products:Ease of useIntegration with other systems
Drawbacks of courseware products:
Formatting and functionality are as provided
Introduction: XML in comparison
Benefits of direct editing:Complete control over appearance and contents
Drawbacks of direct editing:A lot of work formatting contents
Introduction: XML in comparison
XML promises to share some of the benefits of both:
Complete control over appearance and contentsEase of contents creation and maintenance
Additional benefit of XML:Powerful search engines
XML: XML Documents
XML documents contain elementsAn element consists of an opening and closing tagElements are nestedElement names describe contentsElements are not used to format documents
XML: XML Documents
Example:<course_description>
<id>CSSE 100</id> <title>Introduction to Programming and Problem Solving
</title>
</course_description>
XML: DTDs
A DTD defines a class of documentsA DTD specifies:
Elements of the document Attributes of elements Order and nesting of elements Whether elements are necessary
XML: XSL Stylesheets
Used to transform an XML document into an HTML documentXML documents specify which XSL stylesheet is to be used.Web-browser receives XML document and then requests XSL stylesheet
XML: XSL Stylesheets
Uniform appearance of classes of documents: use same stylesheetStylesheet has to be edited just onceSeparation of form and contentsContent providers focus on providing contents
XML: XSL Stylesheets
They are complexDetermine order of presentationLeave out informationLimited amount of processing, e.g. fill in missing information
XML: XSL Stylesheets
Combine information from several documents Minimize repetition of information, by placing common information into separate documentsEnsures consistency of informationReduces amount of nuisance editing
Editing
Separation of form and contents greatly aids in editingContents providers do not have to be concerned about formattingThree ways to edit an XML document:
Edit a template (good)Copy and edit another document (better)Use a forms-based editor (best)
Forms-Based Editor
A web-page with text-fields for XML elementsCustomized to DTDStraight-forward to providePossible to auto-generate
Experience with the Technology
Course description editor is easyTested syllabus editor on 20 studentsEditor works well for structured XML documentsHTML can be added and is properly renderedPreview of documents is being added
Experience with the Technology
Tested course descriptions search engine on 30 studentsOne side of classroom used our XML search engine, other side used Google, restricted to RHITAsked a variety of questions, some favored ours, some favored Google, and some were neutral
Experience with the Technology
“Which courses can I take if I passed CSSE230?” favored XML search“What are the required CS courses for a CS major?” favored Google“What programming languages are used in the CS curriculum?” favored neitherXML searchers turned in their results before Google searchers