Session Number: 5

1
Internet Supply Chain Management ECT 581
Winter 2003
Session Number 5

• Session Date February 4, 2003
• Session Outline
• Administrative Items
• Session Topics XML (continued)
• XML Defined
• XML as a Content Development Tool

2
Session Number 5

• Session Date February 5, 2002
• Session Topics
• XML (continued)
• Session Outline
• Administrative Items
• Session Material

3
Administrative Items

• Web Site Updates
• Initial Exam Homework Results
• Project Information
• Homework Assignment 2

4
XML Development - The Basics

• Include an XML declaration as the first
  statement in an XML document.
• One tag (the root element) contains all of the
  other tags.
• Every element must have a start and an end tag.
• Empty elements must end in /gt
• (Empty elements do not hold content between the
  start and end tags)
• Nesting of tags follow the LIFO rule last tag
  defined is the first tag closed.
• All attribute values are closed in quotes.
• Tags and entities always begin the same way.
• Tags begin with less than (lt) sign.
• Entities begin with an ampersand () sign.

5
XML Essentials DTD Composition

• DTDs consist of the following
• XML declaration tells the processor which
  version of XML to use.
• Document type declaration Tell the processor
  where the DTD is located.
• Element type declaration Defines the element
  type.
• Attribute list declaration defines the name,
  data type, and default value (if any) of each
  attribute associated with an element.
• Entity declaration defines a set of
  information that can be called by using its
  entity name.
• Notation declaration associates a notation
  name with information that can help find an
  interpreter of the notation.

6
XML Entities (continued) Parameter Entity
Example
lt!- Segment from sample Order Form DTD -gt lt!-
Document Structure -gt lt!ELEMENT order (addresses,
lineitems, payment)gt . . lt!- Payment Structure
-gt lt!ELEMENT payment (card PO)gt . .lt!- Card
Structure -gt lt!ELEMENT card (cardholder, number,
expiration)gt lt!ELEMENT cardholder
(PCDATA)gt lt!ELEMENT number (PCDATA)gt lt!ELEMENT
expiration (PCDATA)gt . . lt!- Attribute Rules
-gt lt!ATTLIST card CARDTYPE (VISA Mastercard
Amex) REQUIREDgt
CARDTYPE might show up later in the document as
follows . . ltpaymentgt ltcard
CARDTYPEVISAgt ltcardholdergtJoe
Blowlt/cardholdergt ltnumbergt41280000000000lt/
numbergt ltexpirationgt01/03lt/expirationgt
lt/cardgt lt/paymentgt . . lt/ordergt
7
XML Entities

• In general, an entity is used like an
  abbreviation.
• Entities are primarily structural elements.
• Whereas elements attributes enable
  specification of logical meaning.
• Associates an entity name with a content
  fragment.
• Four types
• Internal parsed allows definition of an alias
  for text fragment.
• External parsed enables inclusion of an entire
  file as part of a document.
• Unparsed enables insertion of arbitrary data
  into a document.
• Parameter enables creation of reusable and
  extensible design elements in a DTD.

8
XML An Example (reprise)

• Using the recipe example, we can create the
  foundation of a DTD.

lt!DOCTYPE recipe lt!ELEMENT recipe (title,
ingredients, directions, body)gt lt!ELEMENT Title
(PCCHAR) lt!ELEMENT ingredients (ingred_amt,
ingred)gt lt!ELEMENT ingred_amt
(PCDATA)gt lt!ELEMENT ingred
(PCDATA)gt lt!ELEMENT directions (mix_instr,
cook_instr, method)gt lt!ELEMENT mix_instr
(PCDATA)gt lt!ELEMENT cook_instr
(PCDATA)gt lt!ELEMENT method
(PCDATA)gt lt!ENTITY wig Wow! Its good so easy
to make!gt gt ltrecipegt lttitlegtDoughlt/titlegt
ltingredientsgt ltingred_amt
gt1 cuplt/ingred_amtgt ltingredgtflourlt/ingredgt
ltingred_amtgt1
tsp.lt/ingred_amtgt ltingredgtsaltlt/ingredgt .
(etc.) lt/recipegt
9
XML Options for Displaying XML
10
Displaying an XML Document Cascading Style
Sheets (CSS)

• Basic Steps for creating CSS
• Create the style sheet.
• Link the style sheet to the XML document.
• If you want to use style sheets, you have to
  tell the browser where to find the stylesheet
  with a statement looking something like this
• lt?xml-stylesheet hrefa_stylesheet.css"
  type"text/css" ?gt

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CSS Example Create the CSS

• Create a file in a text editor (i.e., Notepad,
  WordPad, MS Word, or some other editor)
• For example
• / File Name Memo.css /
• TITLE displayblock margin-top12pt
  font-size10pt
• SUBJECT font-styleitalic
• TO font-weightbold
• FROM font-weightbold
• This initial CSS can be applied to the initial
  XML Memo Document.

12
CSS Example Updated XML Memo Document
lt?xml version"1.0"?gt lt!-- File Name Memo01.xml
--gt lt?xml-stylesheet type"text/css"
href"Memo01.css"?gt lt!DOCTYPE MEMO lt!ELEMENT
MEMO (TITLE, TO, FROM, SUBJECT, BODY, CLOSING,
SIGNATURE)gt lt!ELEMENT TITLE (PCDATA)gt lt!ELEMEN
T TO (PCDATA)gt lt!ELEMENT FROM (PCDATA)gt lt!ELEM
ENT SUBJECT (PCDATA)gt lt!ELEMENT
BODY (PCDATA)gt lt!ELEMENT CLOSING
(PCDATA)gt lt!ELEMENT SIGNATURE
(PCDATA)gt lt!ENTITY to "To "gt lt!ENTITY fm "From
"gt lt!ENTITY sub "Subject "gt lt!ENTITY cls
"Sincerely, "gt gt
ltMEMOgt ltTITLEgtClass Memorandumlt/TITLEgt ltTOgtto
ECT 581 Studentslt/TOgt ltFROMgtfm Ellis
Conferlt/FROMgt ltSUBJECTgtsub My
Errorlt/SUBJECTgt ltBODYgt Somehow, I accidentally
deleted the TITLE element from the DTD example
tags from the original version of this XML
example. It is fixed now. Now we can proceed
with the rest of the lesson. lt/BODYgt ltCLOSINGgtcls
lt/CLOSINGgt ltSIGNATUREgtEllis Conferlt/SIGNATUREgt lt/
MEMOgt
13
CSS Example Create the CSS (continued)

• Lets look at a more advanced CSS applied to the
  updated XML Memo document.
• / File Name Memo01.css /
• TITLE
• color white font-size 14pt
  font-family "Times New Roman" background
  maroon right display block margin-top 12pt
• SUBJECT
• font 18pt "Times New Roman" display
  block margin-top 12pt
• TO
• font-weight bold display
  blockmargin-top 12pt
• FROM
• font-weightbold display block
• BODY font 12pt "Times New Roman" display
  block margin-top 12pt
• CLOSING font 12pt "Times New Roman" display
  block margin-top 12pt
• SIGNATURE font 12pt "Times New Roman"
  display block margin-top 24pt

14
XSL (Extensible Style Language)

• XSL is a language for expressing XML display
  formatting stylesheets.
• It consists of two parts
• 1. a language for transforming XML documents (XSL
  Transformation or XSLT), and
• 2. an XML vocabulary for specifying formatting
  semantics.
• XSLT is a language for transforming XML documents
  into other XML documents.
• An XSL stylesheet specifies the presentation of a
  class of XML documents by describing how an
  instance of the class is transformed into an XML
  document that uses the formatting vocabulary.

15
XSL (continued) Components of XSL Language

• The full XSL language logically consists of three
  component languages
• XPath XML Path Language--a language for
  referencing specific parts of an XML document.
• XSLT XSL Transformations--a language for
  describing how to transform one XML document
  (represented as a tree) into another.
• XSL Extensible Stylesheet Language--XSLT plus a
  description of a set of Formatting Objects and
  Formatting Properties.
• described in three W3C (World Wide Web
  Consortium) Recommendations

16
XSL (continued) Basically, what does a
Stylesheet do?

• A stylesheet specifies the presentation of XML
  information using two basic categories of
  techniques
• An optional transformation of the input document
  into another structure.
• A description of how to present the transformed
  information (i.e., a specification of what
  properties to associate to each of the various
  parts of the transformed information).

17
XSL (continued) - Basically, what makes up a
Stylesheet?

• An XSL stylesheet basically consists of a set of
  templates
• Each template "matches" some set of elements in
  the source tree and then describes the
  contribution that the matched element makes to
  the result tree.
• Generally, elements in a stylesheet in the "xsl"
  namespace are part of the XSL transformation
  (XSLT) language, and non-xsl elements within a
  template are what get put into the result tree.

18
XSL (continued) Description of Info in an XML
Document

• Description of how to present the (possibly
  transformed) data includes three levels of
  formatting information
• Specification of the general screen or page (or
  even audio) layout.
• Note, XSL is usable with different display
  technologies (i.e., HTML, PDF, Postscript).
• Assignment of the transformed content into basic
  "content container types" (e.g., lists,
  paragraphs, inline text)
• Specification of formatting properties (spacing,
  margins, alignment, fonts, etc.) for each
  resulting "container"

19
XSL (continued) Transformation Capabilities

• Transformation capabilities include
• generation of constant text
• suppression of content
• moving text (e.g., exchanging the order of the
  first and last name)
• duplicating text (e.g., copying titles to make a
  table of contents)
• Sorting
• more complex transformations that "compute" new
  information in terms of the existing information

20
What is XSLT?

• XSLT, a subset of XSL, transforms an XML
  document in one format to an XML document in
  another format.
• Responds to the issue of info exchange between
  different organizational entities.
• Manifests as an XSLT transformation document
  which is also an XML document.
• Transformation document resolves differences
  between DTDs.

21
What is XSLT? (continued)
An XSLT "stylesheet" transforms the input
(source) document's tree into a structure called
a result tree consisting of result objects.
22
What is XSLT? (continued)
Example where two different organizations show
parts of order documents in 2 different formats.
XSLT code will perform the transformation.
Document 2 Order currency models currency info
as a child element of the order element ltorder
currencygt ltcurrencygtUSDlt/currencygt ... lt/ordergt
Document 1 Order currency shown as an attribute
on the order element ltorder
currencyUSDgt lt/ordergt
ltxsltemplate match/gt ltxslfor-each
selectordergt ltordergt ltcurrencygt
ltxslvalue-of-select_at_currency/gt
lt/currencygt lt/ordergt ltxslfor-eachgt lt/xslte
mplategt
XSLT transformation document designed to resolve
differences between docs 12.
23
XSLT Example Document as Stylesheet
Simple stylesheet transforms source ltparagt and
ltemphasisgt elements into HTML
STYLESHEET lt?xml version'1.0'?gt ltxslstylesheet
xmlnsxsl"http//www.w3.org/1999/XSL/Transform"
version"1.0"gt ltxsltemplate match"para"gt
ltpgtltxslapply-templates/gtlt/pgt lt/xsltemplategt
ltxsltemplate match"emphasis"gt
ltigtltxslapply-templates/gtlt/igt lt/xsltemplategt
lt/xslstylesheetgt
With STYLESHEET, the following XML
document lt?xml version'1.0'?gt ltparagtThis is a
ltemphasisgttestlt/emphasisgt.lt/paragt Would be
transformed into lt?xml version"1.0"
encoding"utf-8"?gt ltpgtThis is a ltigttestlt/igt.lt/pgt
24
XSL (continued)

• XSL stylesheets consist of 5 major components
• construction rules - these locate elements in the
  document with defined patterns and results or
  actions.
• style rules - these assign characteristics to
  elements in the source document.
• named styles - these define a name for a
  collection of characteristics.
• macros -these define an object with clear
  parameters.
• scripts - these calculate results for use in a
  style attachment.

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XSL (continued) Using XSL

• Basic Steps for using an XSL stylesheet
• Create the XSL style sheet file.
• Link the XSL style sheet file to the XML
  document.
• If you want to use XSL style sheets, you have to
  tell the browser where to find the stylesheet
  with a statement looking something like this
• lt?xml-stylesheet typetext/xsl
  hrefXSLFilePath?gt
• where XSLFilePath is a quoted URL
  indicating the location of the style sheet
  file.
• Note the style sheet file will typically be
  stored in the folder where the xml document
  resides or in one of its subfolders.

26
XSL Example Document as Stylesheet
lthtml xmlnsxsl"http//www.w3.org/1999/XSL/Trans
form"gt ltheadgt lttitlegtSilly Examplelt/titlegt
lt/headgt ltbodygt lth1gtSilly Examplelt/h1gt ltpgtYou'd
probably use extension elements, or something
more interesting in real life 34 is
ltxslvalue-of select"34"/gt. lt/pgt lt/bodygt
lt/htmlgt
27
XSL Example Order Form
lt?xml version1.0gt ltDOCTYPE order SYSTEM
MUSICORDER.DTDgt lt!--Example Order Form for EC
Music Madness--gt lt?xml-stylesheet typetext/xsl
hrefxsldemo.xsl?gt ltorder SOURCEweb
CUSTOMERTYPECONSUMER CURRENCYUSDgt
ltaddressesgt ltaddress ADDTYPEbillshipgt ltfirst
namegtJohnlt/firstnamegt ltlastnamegtSmithlt/lastnamegt
ltstreet ORDER1gt123 Lumpkin
Lanelt/streetgt ltstreet ORDER2gtApt
1Blt/streetgt ltcitygtJohnson Citylt/citygt ltstategtP
Alt/stategt . lt/addressesgt ltlineitemsgt
. . lt/lineitemsgt . . ltpayment
. lt/paymentgt ltordergt
Example of an abbreviated XML-based order form.
28
XSL Example Order Form (continued)
ltxsltemplate matchaddressgt ltfoblock
fofont-sizelarge fofont-weightbold
fofont-familyTimes New Roman
foline-height2 ltxslapply-template/gt lt/fo
blockgt lt/xsltemplategt ltxsltemplate
matchaddress_at_ADDTYPEshipgtgt ltfoblock
fofont-sizesmall fofont-weightnormal
fofont-familyTimes foline-height1
ltxslapply-template/gt lt/foblockgt lt/xsltemplategt
. . .
xsldemo stylesheet (abbreviated version) can be
applied to affect the display of specific
elements.
Note fo refers to formatting object. For more
info please refer to the following
link http//www.w3.org/TR/xsl/slice6.htmlfo-sect
ion
29
XML Namespaces

• XML namespaces are designed to provide
  universally unique names for elements and
  attributes. This allows people to do a number of
  things, such as
• Combine portions from different documents and,
  thereby, avoid any naming conflicts.
• Write code modules that can be invoked for
  specific elements and attributes.
• Define elements and attributes that can be
  reused in other schemas or instance documents
  without fear of name collisions.
• The XML namespaces defines a way to distinguish
  between duplicate element type and attribute
  names.

30
XML Namespaces (continued)

• Example accounting fulfillment application
  both want to use status as a keyword.
• Attaching namespace to an element or attribute
  name links it with namespace.
• Namespace names for department can be declared
• ltacctcustomer xmlnsaccthttp///www.blahcompany.
  com/names/acct-deptstdsgt
• ltacctnamegtFriendly Corplt/acctnamegt
• ltacctaddresseegtltAccounts Payable-Friendly
  Corplt/acctaddresseegt
• ltacctorder acctreference2222-1001gt
• ltacctstatusgtinvoicelt/acctstatusgt
• lt /acctordergt
• lt/acctcustomergt
• ltfulcustomer xmlnsfulhttp///www.blahcompany.co
  m/names/ful-deptstdsgt
• ltfulnamegtFriendly Corplt/fulnamegt
• ltfuladdresseegtltLoading Docklt/fuladdresseegt
• ltacctorder acctreference2222-1001gt
• ltfulstatusgtshippedlt/fulstatusgt
• lt /fulordergt
• lt/fulcustomergt

31
XML Namespaces Five Bullets

• The XML namespaces recommendation defines a way
  to distinguish between duplicate element type and
  attribute names. Such duplication might occur,
  for example, in an XSLT stylesheet or in a
  document that contains element types and
  attributes from two different DTDs.
• An XML namespace is a collection of element type
  and attribute names. The namespace is identified
  by a unique name, which is a URI. Thus, any
  element type or attribute name in an XML
  namespace can be uniquely identified by a
  two-part name the name of its XML namespace and
  its local name. This two-part naming system is
  the only thing defined by the XML namespaces
  recommendation.
• XML namespaces are declared with an xmlns
  attribute, which can associate a prefix with the
  namespace. The declaration is in scope for the
  element containing the attribute and all its
  descendants. For example
• lt!-- Declares two XML namespaces. Their scope is
  the A and B elements. --gt ltA xmlnsfoo"http//www
  .foo.org/" xmlns"http//www.bar.org/"gt
  ltBgtabcdlt/Bgt lt/Agt

32
XML Namespaces Five Bullets (continued)

• If an XML namespace declaration contains a
  prefix, you refer to element type and attribute
  names in that namespace with the prefix. For
  example
• lt!-- A and B are in the http//www.foo.org/
  namespace, which is associated with the foo
  prefix. --gt ltfooA xmlnsfoo"http//www.foo.org/"
  gt ltfooBgtabcdlt/fooBgt lt/fooAgt
• If an XML namespace declaration does not
  contain a prefix, the namespace is the default
  XML namespace and you refer to element type names
  in that namespace without a prefix. For example
• lt!-- This is equivalent to the previous example
  but uses a default namespace instead of the foo
  prefix. --gt ltA xmlns"http//www.foo.org/"gt
  ltBgtabcdltBgt lt/Agt

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Next Session Highlights

• XML (continued)
• Next Session Reading Assignment
• Review chapter 2 of Fitzgerald text
• Skim chapters 6-9 of Fitzgerald text
• Read chapter 10 of Fitzgerald text
• Web sites (linked thru the class notes web site)
• CSS Tutorial (recommended)