Foundation Course on XML - Ravindra Godbole XML Extensible Markup Language

Foundation Course on XML

- Ravindra Godbole

XML

Extensible Markup Language

Any comments !

Everyday Impact of XML ...

Jack and Jill

Jack and JillWent up the HillTo fetch a pell of water

Jack fell down and broke his crownJill came tumbling after

Anonymous

What was that ? It’s a Poem It has title It has stanzas. It is written by somebody ( anonymous )

This interpretation though possible for humans is notpossible for computers.

Poem using Markup Language

<poem><title> Jack and Jill </title><stanza>

Jack and JillWent up the HillTo fetch a pell of water

</stanza>

<stanza>Jack fell down and broke his crownJill came tumbling after

</stanza><author>Anonymous</author>

</poem>

After this presentation you will .. Know XML concepts be able to write XML using simple

editor be able to write DTD for an XML learn use of XSL know what is Document Object Model Enjoy learning more about XML

Technologies

Pre-requisites

OOPs HTML Java

Knowledge of following will be helpful, but it is not mandatory.

We will cover ...

• Introduction to XML• Use of XML • XML Syntax• DTD• XSL• Document Object Model

HTML and XMLHTML only addresses the presentation of data.

XML takes this one step further, by addressing the contextor meaning of the data.

Example

Using XML, the word “bill” can be tagged as a name, a charge, a paper currency,a proposed law, or the mouth of a bird.

Any other examples ?

XML is a simple data format that balances the needs of

people to read/write data with the needs of machines

to read/write data.

Introduction to XML

What is XML ?

XML is a text based meta-language. It is usedto define other Markup languages.

Example of Markup Languages

• MathML• WML

XML is not ..

A Programming Language

Introduction to XML….

XML is a method for putting structured data in a text file .

Here is a example of XML file - book.xml<?xml version=“1.0”><booklist>

<book><name>XML Specification</name><author>Ian Grahm</author>

</book><book>

<name>A Mythical Man Month</name>

<author>Fredrick Brooks Jr.</author></book><book>

<name>More Effective C++</name><author>Scott Mayers</author>

</book></booklist>


XML looks a bit like HTML but isn't HTML

XML uses tags ( words separated by <,>) and attributes just like HTML. But HTML uses these tags for displayinginformation in the browser.

XML uses these tags, only to delimit pieces of data andleaves the interpretation of data completely to the applicationthat reads it.

So XML is not HTML


XML is text, but isn't meant to be read

• XML files are text files. But these are to be edited only during emergencies.

• A forgotten tag, or an attribute without quotes makes the XML file unusable.


XML is verbose, but that is not a problem

XML is a text format, and it uses tags to delimit the data, XML files are nearly always larger than comparable binary formats.

This is not a issue now a days as disk space is not expensive. Alsolots of compression utilities are widely available and modern protocolslike HTTP/1.1 can compress data on the fly.


XML is license-free, platform-independent and well-supported

Many new tools and technologies are available to support XML activity.

You can build your software around it without paying anybody anything.

You are not tied to single vendor.

XML Users Microsoft IBM Netscape Sun Microsystems Adobe Corel Hewlett-Packard


XML Resources on the web

• http://xml.com/• http://www.ibm.com/xml/• http://www.sun.com/xml/• http://www.w3.org/

Use of XML

Use of XML

Use of XML

XML-Enabled Technologies

• Internet Search Engines• Electronic Commerce• Electronic Data Interchange ( EDI )• Data Repurposing• Content Personalization

and many more ...

Use of XML

Internet Search Engines

Due to power of XML, data could be tagged properly.This will enable search engines to retrieve exact information.

Searching for information about the Java programming language would no longer yield links to coffee sites or the Island of Java. This is because searching for theterm “Java” is narrowed down to those fields tagged as a “programming language”.

When searching for information on a subject that is contained in a single chapter or even a single page within a book, XML enables you to retrieve only that chapteror page, while HTML currently gives you the entire book.

Use of XML

Electronic Data Interchange

By leveraging XML, the applications easily broker information between themselves. Mapping data from one company’s purchasing system to another company’s inventory is just a matter of understanding the XML tags on the data.

Existing

A

D

B

C

Using XML

A

C

B

D

XML

Data Exchange

Use of XML

Electronic Commerce

With XML repository technology, on-line stores can present product information in a standard, structured format, independent of page design.

By reducing the time needed to locate a product, a price, or any otherrelevant information on the Internet, XML repositories will play an important role in making on-line shopping more efficient and enjoyable.

Use of XML

Data Repurposing

By breaking documents into discrete elements, it becomes very easy for individuals to extract the truly relevant information from several sources.

They can reassemble it into any format (e.g. web page, document, presentation, whatever).

XML Document- A XML Document - B

New Document

Use of XML

Content Personalization

Using XML, you could create a very sophisticated personal news filter that spans multiple sites or the entire Internet. The XML repository would provide the date stamp, enabling agents or search engines to filter the information to extract only the “new” information.

Multiple formatting of XML

XML Document Online Help

HTML

Braille

Plain Text

Formatter

Formatter

Formatter

Formatter

Building XML Documents


Logical and Physical Views of XML document

booklist

publishername

bookbook book book

author

location

Book.xml

Book2.xmlBook1.xml

Name.xmlAuthor.xml

Logical View Physical View


XML file always start with a prolog.

The minimum prolog contains a declaration that identifiesthe document as XML document like this.

<?xml version="1.0"?>

The declaration might contain additional information whichwe will study later.

Identifies version of XML markup language used. This attribute is mandatory

Declaration

XML Keywords ELEMENT DOCTYPE ATTLIST NOTATION ID IDREF

W ell F orm ed XML

Valid XML

Ch aracter Data an d Marku p

Com m en ts

Processin g In stru ction s

CDATA section s

W h ite sp ace Han d lin g

D ocu m en t

Start, En d , Em p ty Tag s

E lem en t Typ e Declaration s

Attrib u te List Declaration

Con d ition al Section s

L og ica l S tru c tu re

Ch aracter Referen ces

En tity Referen ces

En tity Declaration s

Parsed En tites

P rocessin g In stru ction s

Notation Declaration

P h ys ica l S tru c tu re

X M L

1. Well-formed

2. Valid

Well-formed documents conform with XML syntax.They contain text and XML tags. Everything is enteredcorrectly. They do not, however, refer to a DTD.

Valid documents not only conform to XML syntax but they also are error checked against a Document TypeDeclaration.

Type of XML Document

Well Formed XML Document Has one or more elments Has exactly one element called the

root or document element. Meets all the requirement for

specification

Building XML Documents - Example

<?xml version=“1.0” encoding=“UTF-8” standalone=“yes”><booklist>

<book><name type=“spec”>XML Specification</name><author>Ian Grahm</author>

</book><book>

<name>A Mythical Man Month</name><author>Fredrick Brooks Jr.</author>

</book>

<listbreak/>

<book><name>More Effective C++</name><author>Scott Mayers</author>

</book></booklist>

Well formed XMLdocument



<book><name type=“spec”>XML Specification<author>

</name>Ian Grahm</author>

</book><book>

<name>A Mythical Man Month</Name><author>Fredrick Brooks Jr.</author>

</book><listbreak/><book>


</book></booklist>

NOTWell formed XML

documentTAGs do notnest properly.

Also Case does notmatch.

Valid XML Document

• Is well formed• Meets all the requirements specified in the Document Type Declaration

Well Formed XML

Valid XML

Character data All text that is not markup constitutes the character data of the Document. In the content of elements, character data is any string of characters which does not contain

the start-delimiter of any markup. In a CDATA section, character data is any string of characters not including the CDATA-

section-close delimiter, "]]>".

Markup Markup takes the form of

start tags end tags empty element tags entity references character references comments CDATA section Processing Instructions


<?xml version=“1.0”><booklist>


</book><book>


</book><book>


</book>

</booklist>

Start tag denotesbeginning of

element.




</book><book>


</book><book>


</book>

</booklist>

End tag denotesend of

element.




</book><book>


</book><book>


</book>

</booklist>

Start and end tag must match,

nest and can notoverlap.




</book><book>


</book>

<listbreak/>


</book></booklist>

Empty element tagcan not contain anyother markup or text

Comments Comments may appear anywhere

in the document outside other markup

They are not part of the document’s character data




</book><book>


</book><listbreak/><book>


</book></booklist>

XML commentsare entered like this.

Start tag is 

Processing Instructions Processing Instructions allow

document to contain instructions for application.

The TARGET name XML and xml are reserved for future use.

<?target instructions?>

target is the name of the application that is expected to do the processing,

instructions is a string of characters that embodies the information or commands for the application to process

Writing XML - Processing Instructions

Processing Instructions Example

<?xml-stylesheet type="text/xsl" href="cd_catalog.xsl"?>

Writing XML - CDATA

CDATA sections are used to display markup without the XML processor trying to interpret that markup. They are particularly useful when you want to display sections of XML code.

CDATA sections.

<![CDATA[

<greeting>Hello, world!</greeting>]]>

White Space Handling White spaces are sometime redundant May be needed in contents like poetry ,

source code Special attribute to indicate the

intention of data regarding white space - xml:space

<!ATTLIST poem xml:space (default|preserve) 'preserve'>

This applies to all elements of the content, unless overriddenagain with another instance of xml:space attribute.


DTD - Document Type Declaration

The DTD defines the elements, attributes, and relationships

between elements for an XML document.

A DTD is a way to check that the document is structured correctly, but presence of DTD in a document is optional.

Here, file address.dtd which contains all the rules and is included in address.xml as follows...

<!DOCTYPE addressbook SYSTEM ”address.dtd" >

XML and DTD

XML

DTD

XML Parser

ValidXML

Invalid XMLXML Parsers

• MSXML• AlphaWorks• XP

yes

no

XML - Writing DTD

Document is compared against associated DTD tocheck for its correctness.

This process is called validation and is performed by a tool called Parser.

XML - Writing DTD

Need for DTD

• All documents in a group follow the same set of rules.• Ensure that all the data required is present.• Need to match to Industry-specific standards.• Error-check the document for accuracy of tag usage.

XML - Writing DTD

Deciding on DTDs

• Share a DTD• Create your own DTD• Make an Internal DTD

XML - Writing DTD

Each statement in a DTD uses the <!XML DTD> syntax. This syntax begins each instruction with a left angle bracket and an exclamation point, and ends it with a right angle bracket.

Our outermost tag is booklist.

<!ELEMENT BOOKLIST (BOOK)+>

W ell F orm ed XML

Valid XML


Com m en ts


CDATA section s


D ocu m en t



Attrib u te List Declaration




En tity Referen ces


Parsed En tites




X M L


Tag

You use a tag to identify a piece of data by element name.

Tags usually appear in pairs, surrounding the data. The opening tag contains the element name. The closing tag contains a slash and the element's name, like this:

<name>Effective C++</name>

Tag

Writing XML - Element Type Declaration

Element Type Declaration

Element type declarations set the rules for the type and number of elements that may appear in an XML document, what elements may appear inside each other, and what order they must appear in.


<!ELEMENT parent_name (child_name)>

<!ELEMENT child_name allowable content>

<?xml version="1.0"?><!DOCTYPE student [  <!ELEMENT student (id)>  <!ELEMENT id (#PCDATA)>]><student> <id>9216735</id></student>


Mixed content

Mixed content is used to declare elements that contain a mixture of children elements and text

<?xml version="1.0"?><!DOCTYPE student [ <!ELEMENT student (#PCDATA|id)*> <!ELEMENT id (#PCDATA)>]><student> Here's a bit of text mixed up with the child element. <id>9216735</id> You can put text anywhere, before or after the child element. You don't even have to include the 'id' element.</student>

W ell Form ed XML

Valid XML


Com m en ts


CDATA section s


D ocu m en t



Attribu te L ist Declaration




En tity Referen ces


Parsed En tites




X M L


Attribute

Attributes are like adjectives, in that they further describe elements. Each attribute has a name and a value.

Attributes are entered as part of the tag, like this:

<name number="1874">XML Specification</name>

number is attribute of name


Types of Attribute

• STRING• ENUMERATED• ID• IDREF/IDREFS• ENTITY/ENTITIES• NMTOKEN• NOTATION

Building XML Documents - Attribute types

String type

Indicated by the keyword CDATA

Any string of valid XML character is allowed withthese restriction

Can not contain quotation, < and &

<!ATTLIST menu date CDATA #REQUIRED time CDATA #IMPLIED >


Enumerated-List type

List of possible values which attribute can take.

<!ATTLIST item type ( appetizer | entrée | dessert ) “entrée”

These definitions can also use #FIXED #IMPLIED or#REQUIRED default declarations.

NOTATION Notations identify by name the

format of unparsed entities, format of element which bear NOTATION attribute, or the application to which processing instruction is addressed.


Notation Attributes

These are enumerated type of attributes that can only take as allowed values, one of the defined list of Notations.

<!ATTLIST frogs imgtype NOTATION ( gif|jpeg|pict) “gif” encoding NOTATION ( uuencode|base64) “base64”>

<frogs imgtype=“gif” encoding=“base64”>


ID Attribute Type

Designed for labeling and referencing elements in XML.

<!ATTLIST item ref ID #REQUIRED>

<item ref=“newItem”>abcd….</item>

newItem value should be unique within the document.


IDREF and IDREFS Attribute type

Used to reference elements labeled by ID attributes.

<!ATTLIST itemsize ref-to IDREF #IMPLIED topref IDREF #REQUIRED ><itemsize ref-to=“xs-089” topref=“dds-ss”>this is a item</itemsize>

All referenced ID must be present within the document.


IDREFS are equivalent to IDREF in that it can take morethan one references.

<!ATTLIST itemizers topref IDREFS #FIXED “ref1 ref2 ref43”>

IDREF(S) can be used to link one section of document withother, such as footnote or glossary entry.

Conditional Sections

Conditional sections are portions of the the DocumentType Declaration external set, which are included in, or excluded from, the logical structure of the DTD based on the keyword which governs them.

Example of Conditional Sections

<!ENTITY % draft 'INCLUDE' ><!ENTITY % final 'IGNORE' >

<![%draft;[<!ELEMENT book (comments*, title, body, supplements?)>]]><![%final;[<!ELEMENT book (title, body, supplements?)>]]>

XML Document - Example



</book><book>


</book><book>


</book>

</booklist>

Can you write simple XML Document ?

1. Building2. Employee3. Computer4. Car

W ell F orm ed XML

Valid XML


Com m en ts


CDATA section s


D ocu m en t



Attrib u te L ist Declaration




En tity Referen ces


Parsed En tites

P rocessin g In stru ction s



X M L

Physical Structure XML document may contain one or

more storage units called entities. Entities may be either parsed or

unparsed.

XML - Writing DTD

Entity Declarations

Entities reference data that act as an abbreviation or can be foundat an external location.

• Entities reduce entry of repetitive information• Entities allow us easier editing.

Types of Entities

• General• Parameter

• Parsed• Unparsed

• Internal• External

XML - Writing DTD - Entity Declaration

These entities refer to data which XML processor has to parse.

<!ENTITY name "entity_value">

<?xml version="1.0" standalone="yes" ?><!DOCTYPE author [ <!ELEMENT author (#PCDATA)> <!ENTITY js "Jo Smith">]><author>&js;</author>

General Entities - Internal Parsed Entities


External Entities

External entities are useful for creating a common reference that can be shared between multiple documents.

<!ENTITY name SYSTEM "URI">

<?xml version="1.0" standalone="no" ?><!DOCTYPE copyright [ <!ELEMENT copyright (#PCDATA)> <!ENTITY c SYSTEM "http://www.xmlwriter.net/copyright.xml">]><copyright>&c;</copyright>


External UnParsed Entities

External unparsed entities generally reference non-XML data. The 100% correct definition is that they refer to data that an XML processor does not have to parse.

<!ENTITY name SYSTEM "URI" NDATA name>

<?xml version="1.0" standalone="no" ?><!DOCTYPE img [ <!ELEMENT img EMPTY> <!ATTLIST img src ENTITY #REQUIRED> <!ENTITY logo SYSTEM "http://www.xmlwriter.net/logo.gif" NDATA gif> <!NOTATION gif PUBLIC "gif viewer">]><img src="logo"/>


Using Entities within Entities

<?xml version="1.0"?><!DOCTYPE author [ <!ELEMENT author (#PCDATA)> <!ENTITY email "[email protected]">

 <!ENTITY js "Jo Smith &email;">]><author>&js;</author>


Predefined Entities

Predefined entities How to declare these entities in a DTD:

< <!ENTITY lt "<">

> <!ENTITY gt ">">

& <!ENTITY amp "&">

' <!ENTITY apos "'">

" <!ENTITY quot """>


Parameter Entities• Internal ( Parsed ) • External ( Parsed )

Internal parameter entity references are used to declare entities existing only in the DTD.

<!ENTITY % name "entity_value">

<!ENTITY % p "(#PCDATA)"><!ELEMENT student (id,surname,firstname,dob,(subject)*)><!ELEMENT id %p;><!ELEMENT surname %p;><!ELEMENT firstname %p;><!ELEMENT dob %p;><!ELEMENT subject %p;>


External Parameter Entites

External parameter entity references are used to link external DTDs.

<?xml version="1.0" standalone="no"?><!DOCTYPE student [ <!ENTITY % student SYSTEM "http://www.university.com/student.dtd"> %student;]>

XML revisited...




</book><book>


</book><book>


</book>

</booklist>




</book><book>


</book><book>


</book>

</booklist>

XML declaration saysthat data that follows is an XML document.




</book><book>


</book><book>


</book>

</booklist>

Top level elementcalled root element.Contains all other

elements.Only one root element

per document




</book><book>


</book><book>


</book></booklist>

These elements are inside the root

element.




</book><book>


</book><book>


</book>

</booklist>

Document complieswith version 1.0 ofXML Specification


booklist

book

authorname

book

authorname




</book><book>


</book><book>


</book>

</booklist>

Start tag denotesbeginning of

element.




</book><book>


</book><book>


</book>

</booklist>

End tag denotesend of

element.




</book><book>


</book><book>


</book>

</booklist>

Start and end tag must match,

nest and can notoverlap.




</book><book>


</book><book>


</book>

</booklist>

Data is enclosedby the start and end

tags.




</book><book>


</book>

<listbreak/>


</book></booklist>

Data in this fileis encoded

using UTF-8encoding.




</book><book>


</book>

<listbreak/>


</book></booklist>

This document canbe read and processed

independentof any external

entities.




</book><book>


</book>

<listbreak/>


</book></booklist>

Attributes are simplynamed quantities

that define propertiesabout a specificinstance of an

element.




</book><book>


</book><listbreak/><book>


</book></booklist>

XML commentsare entered like this.

Start tag is 




</book><book>


</book>

<listbreak/>


</book></booklist>

Empty element tagcan not contain anyother markup or text

Rules to remember

• Remember XML declaration• Do what the DTD instructs.• Watch your capitalization• Quote attribute values• Close all tags• Close empty tags too.

Case Study 1 Identify Element Identify Attribute Write DTD Write XML

Case Study 2 Identify Element Identify Attribute Write DTD Write XML

So far we covered... XML Concepts Use of XML Writing XML document Writing DTD

Standards built on XML MathML WML

MathML

MathML is about encoding the structure of mathematical expressions so that they can be displayed, manipulated and shared over the World Wide Web

A carefully encoded MathML expression can be evaluated in a computer algebra system, rendered in a Web browser, edited in your word processor, and printed on your laser printer.

There are about 100 markup elements for MathML

MathML Example

<msup> <mfenced> <mrow> <mi>a</mi> <mo>+</mo> <mi>b</mi> </mrow> </mfenced> <mn>2</mn></msup>

( a + b ) 2

is represented in MathML as

WML ( Wireless Markup Language )

• Markup Language mainly used by WAP aware browsers• Must conform to DTD http://www.wapforum.org/DTD/wml_1.1.xml

WML Example

<?xml version="1.0"?> <!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml"> <wml> <card id="Card1" title="Wap-UK.com">  Hello World </card> </wml>

Click here to learn more about WML

XML Examples• xml 1• xml 2• xml 3• xml 4• xml 5• xml 6• xml 7

DTD Examples

• Play• Song• Genbank

XML Test Bed

Now its time to have some hands on XML.

Click here to invoke the XMLTestbed Applet

XML data usage…. Using CSS ( Cascading Style

Sheet ) XSL

We need Internet Explorer 5 to view these catalog.xml files.

1. XML viewing using style sheet catalog.css2. XML viewing with XSL uses cd_catalog.xsl3. Ordered list of CDs using XSL 4. Filtering XML data using XSL

Web basedXML App.

Use of XML at DrKB, London

XML as an alternative to dynamically changing

specifications.

XML Namespaces

An XML namespace is a collection of names that can be used as element or attribute names in an XML document.

XML Nampspace.. Identified by

URI ( Universal Resource Identifier ) URL ( Unique Resource Locator ) URN ( Unique Resource Number

Namespaces Declarations

• Explicit• Default

<BOOKS> <bk:BOOK xmlns:bk=”http://booklovers.org" xmlns:money=”http://finance.com"> <bk:TITLE>A Suitable Boy</bk:TITLE> <bk:PRICE money:currency="US Dollar">22.95</bk:PRICE> </bk:BOOK></BOOKS>

Explicit Namespace declaration

Define a shorthand, or prefix, to substitute for the full name of the namespace.

Are useful when a node contains elements from different namespaces

Declaring default namespace

The following example declares the "BOOK" element and allelements and attributes within it ("TITLE", "PRICE", "currency") are from the namespace ”http://book.info.com"

<BOOK xmlns=”http://book.info.com"> <TITLE>A Suitable Boy</TITLE> <PRICE currency="US Dollar">22.95</PRICE></BOOK>

<?xml version="1.0"?><book xmlns='urn:loc.gov:books'xmlns:isbn='urn:ISBN:0-395-36341-6'><title>Cheaper by the Dozen</title><isbn:number>1568491379</isbn:number><notes>This is a funny book!</notes></book>

Let’s see Document Object Model ...

DOM

Document Object Model


• What is DOM ?• DOM - XML Parser• DOM Usage


DOM - Document Object Model is a set of interfaces defined by W3C.


DOM interface is platform and language independent

These interfaces represent structure and content of XMLdocuments.


DOM Object Types XML Document is represented as

collection of Node Objects. Node types are as follows.

Document Node Element Node Attribute Node Text Node Comment Node Processing Instruction Node


Most commonly used Nodes

Node Type Example

• Document <!DOCTYPE book SYSTEM “book.dtd”>• Processing Instruction <?xml version=“1.0”?>• Element <name type=“design”>A Mythical Man Month</name>• Attribute type=“design”• Text A Mythical Man Month

Using JAVA to access DOM IBM Alphaworks DOM implementation is used here. Let’s walk through the java code.

public static void main (String args[]) {

// File reading syntax…..

Parser parser = new Parser(filename); //*** Note how we refer only to DOM Interface references.

Document doc = parser.readStream(is);

Element root = (Element)doc.getDocumentElement(); //*** Use DOM Interface references. traverse(root);

}

public static void traverse(Node node){

// Check the current Node

System.out.println( node.getNodeName() + " - " + node.getNodeType() + " - " +

node.getNodeValue()) ;

// Print more information for child Nodes

if (node.hasChildNodes()) { NodeList nl = node.getChildNodes(); int size = nl.getLength(); for (int i = 0; i < size; i++) { traverse(nl.item(i)); } }

XSL

eXtensible Style Language

Purpose of XSL

To provide, powerful yet easy-to-use style sheet syntaxfor rendering XML Document.

XML XSLStylesheet

XSL Processor

XSL Processor

XSL Processor

RTF

Tex

HTML

XSL Architecture XSL style sheet has set of rules known

as construction rules. It converts data into set of objects

known as flow objects. Common flow objects are

Page,Paragraph,Table,etc. Flow objects have characteristics. XSL is itself an XML document and is

based on its own DTD. It has a handful set of element types.

XSL Transformations Uses style sheet language XSL to transform

XML Transformed XML can be another XML

document which may be used for viewing or for some other purpose

Transformations in XSLT describe rules for transforming source tree into result tree.

Transformation is achieved by associating patterns with templates.

The structure of the result tree can be completely different from the source tree.

XSL …..Stylesheet

• Contains set of template rules• Template tree contains pattern and template rule to implement when pattern is found.• While searching the elements, XSLT makes use of expression language defined by XPath.

XSL ….. StyleSheet has the following structure

Stylesheet Structure

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:template match="..."> ...

</xsl:template>

<xsl:template name="..."> ...

</xsl:template>

</xsl:stylesheet>

XSL …..

<?xml version='1.0'?><xsl:stylesheet xmlns:xsl="http://www.w3.org/TR/WD-xsl"><xsl:template match="/"><html><body><xsl:value-of /></body></html></xsl:template></xsl:stylesheet>

Example

This will print the whole xml document.

XSL …..

Example

<xsl:template match="title"> <xsl:value-of /> </xsl:template>

Computing Value of Node

XSL …..Processing Multiple Elements

Example<xsl:template match="bookstore"> <body> <xsl:for-each select="book"> Title:<xsl:value-of select="title"/> Price:<xsl:value-of select="price"/> </xsl:for-each> </body></xsl:template>

XSL …..XML Patterns

Selecting nodes starting from root through XML hierarchy

bookstore/book/titleWildcard used for unknown elements

/bookstore/*/titleHaving a specified element

/bookstore/book/author[first-name]Selecting attribute of an element

/bookstore/book/@genreSpecifying attribute with given value

/bookstore/book/@genre="autobiography"

XSL …..

XSL Transformation Specification

Simple XSL Examples cd_catalog cd_catalog_filter cd_catalog_order

Case Study

Write XML for employee of company

and use the same file for various departments like

personnel,travel,finance,projects,etc.

Use existing XSL / CSS to display the data.

Quiz !

Some points to think about …..

Quiz Where did XML get its Name ? What does it do ? What is markup Language ? Why markup languages have to base on XML ? What is structured Document ? How do you check the structure of XML for

validity ? Where can XML be used ? Give example of Markup Languages based on

XML ?

<? Quiz ?>

Is the following xml declaration correct ?<Elem type=“type1” Type=“input”>

<!ELEMENT myMoney ( #PCDATA | currancy | currancy | visa ) * >

<!ELEMENT name (first, last)><!ELEMENT name (first, middle,last)>

Can we make any content of element as integerby putting some constraint ?

<? Quiz ?>

Can we use PCDATA as element name in XML?

Xml FAQs are useful for understanding some subtlepoints.

Thank You