Transcript Logical Structure of XML Documents

Introduction to the Logical
Structure of XML Documents
Web Engineering, SS 2007
Tomáš Pitner, Michael Derntl
Example of an XML Document
<?xml version='1.0' encoding='UTF-8'?>
<staff organization="Bundesregierung">
<person id="agu">
<name>Alfred Gusenbauer</name>
<party url="http://www.spoe.at">SPÖ</party>
</person>
<person id="wmo">
<name>Wilhelm Molterer</name>
<party url="http://www.oevp.at">ÖVP</party>
</person>
</staff>
XML Document – Prolog/Heading
<?xml version='1.0' encoding='UTF-8'?>
<staff organization="Bundesregierung">
<person id="agu">
Version:
<name>Alfred Gusenbauer</name> Character
typically 1.0
encoding: UTF<party url="http://www.spoe.at">SPÖ</party>
8, UTF-16, US</person>
XML
Prolog
ASCII always
<person id="wmo">
work!
<name>Wilhelm Molterer</name>
<party url="http://www.oevp.at">ÖVP</party>
</person>
</staff>
XML Document - Root Element
<?xml version='1.0' encoding='UTF-8'?>
<staff organization="Bundesregierung">
<person id="agu">
<name>Alfred Gusenbauer</name>
<party url="http://www.spoe.at">SPÖ</party>
</person>
<person id="wmo">
<name>Wilhelm Molterer</name>
Root element contains most
<party url="http://www.oevp.at">ÖVP</party>
</person>
</staff>
of the information in the doc,
every doc must have exactly
one root element!
Elements and Tags
Element
Element
Name
<?xml version='1.0'
encoding='UTF-8'?>
<staff organization="Bundesregierung">
<person id="agu">
<name>Alfred Gusenbauer</name>
<party url="http://www.spoe.at">SPÖ</party>
</person>
<person id="wmo">
Start Tag of the element
<name>Wilhelm Molterer</name>
<party url="http://www.oevp.at">ÖVP</party>
</person>
</staff>
End Tag of the element
Attributes
Attribute: placed in the
<?xml
version='1.0'
encoding='UTF-8'?>
element's
start tag
<staff organization="Bundesregierung">
<person id="agu">
<name>Alfred Attribute
Gusenbauer</name>
Value: in single or double quotes!
<party url="http://www.spoe.at">SPÖ</party>
</person>
<person id="wmo">
Note: multiple Attributes are
separated through whitespace
<name>Wilhelm Molterer</name>
<party url="http://www.oevp.at">ÖVP</party>
</person> Attribute Name: unique
</staff>
within an element!
Element Content: Text Nodes
<?xml version='1.0' encoding='UTF-8'?>
<staff organization="Bundesregierung">
<person id="agu">
<name>Alfred Gusenbauer</name>
<party url="http://www.spoe.at">SPÖ</party>
Element
</person>
<person id="wmo">
<name>Wilhelm Molterer</name>
<party url="http://www.oevp.at">ÖVP</party>
</person>
</staff>
Element Content: Text Node
Element Content: Child Elements
(Parent)
<?xml Element
version='1.0' encoding='UTF-8'?>
<staff organization="Bundesregierung">
<person id="agu">
<name>Alfred Gusenbauer</name>
<party url="http://www.spoe.at">SPÖ</party>
</person>
<person id="wmo">
<name>Wilhelm Molterer</name>
<party url="http://www.oevp.at">ÖVP</party>
</person>
</staff>
Element Content: Child Elements
XML Document with DTD
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE staff SYSTEM "staff.dtd">
<staff organization="Bundesregierung">
<person id="agu">
<name>Alfred Gusenbauer</name>
Root element
System identifier
<party url="http://www.spoe.at">SPÖ</party>
name
</person>
<person id="wmo">
(URI) of the
entity/file with
<name>Wilhelm Molterer</name>Document Type
<party url="http://www.oevp.at">ÖVP</party>
Definition
</person>
</staff>
Document Type
Declaration
XML Document with Comment
<?xml version='1.0' encoding='UTF-8'?>
<!-- Comment content -->
<!DOCTYPE staff SYSTEM "staff.dtd">
<staff organization="Bundesregierung">
<person id="agu">
Comment
<name>Alfred Gusenbauer</name>
content
<party url="http://www.spoe.at">SPÖ</party>
</person>
<person
Commentid="wmo">
(-node):
<name>Wilhelm Molterer</name>
usually
not interpreted
<party url="http://www.oevp.at">ÖVP</party>
by the application
</person>
</staff>
Processing Instructions
<?xml version='1.0' encoding='UTF-8'?>
<?xml-stylesheet href="style.css" type="text/css"?>
<!DOCTYPE staff SYSTEM "staff.dtd">
<staff organization="Bundesregierung">
<person id="agu">
PI Target
PI Data (no attributes!)
<name>Alfred
Gusenbauer</name>
<party url="http://www.spoe.at">SPÖ</party>
</person>
<person id="wmo">
<name>Wilhelm Molterer</name>
<party url="http://www.oevp.at">ÖVP</party>
</person>Instruction:
Processing
</staff>
interpretation depends on
application