1. CIS-189

2.  XSL stands for Extensible Stylesheet
◦ Stylesheets are used to manage organization and
presentation of data
 Implemented as an XML language
◦ Rules of XML apply
 Made up of
◦ XSL-FO (Formatting Objects)
◦ XSLT (Transformations)

3.  XSL-FO focused on presentation to screen
and paper
◦ Not well-supported by browsers
 XSLT emphasizes re-organization of data
◦ Typically used for presentation but can also be used
for conversion of data storage format
◦ XSLT is a declarative language
 Similar to SQL, describe results not steps

4.  Cascading Style Sheets used to separate
presentation from data
 XSLT used to change – transform – data
◦ Convert an XML document to XHTML
 Can use both together

5. XSL requires several steps
1. XML processor reads document
◦ Creates document tree
2. XSL processor applies rules from stylesheet
◦ Rules applied to document tree
◦ Rules applied by using pattern matching
 Identify nodes to apply rules to
◦ Rules are stored as templates

6.  XSL works by using an Input Tree
◦ Input Tree comes from XML processor
 Process of changing input values is call Tree
Transformation
 Result of transformation is the Result Tree
◦ Result Tree can include
 XML
 HTML (must adhere to XML rules, i.e., XHTML)
 Formatting Objects

7.  Extensible Stylesheet Transformations is
method of changing (transforming) XML
based on rules of a stylesheet
 Xpath allows manipulation of parts of XML
document
◦ Not XML-based
◦ Provides compact references
 Useful in URI’s, attributes
◦ Document must exist as nodes (previously parsed)

8.  Templates are definitions of rules,
organization
 Patterns define values searching for (where to
apply templates)
 Expressions allow use of functions using
nodes as inputs
 When referring to document attributes
preface name with “@”

9.  <xsl:stylesheet> is root element
◦ Uses namespace to define elements, attributes valid
in a stylesheet
 <xsl:template> defines the rules/
transformations to apply
◦ Match attribute specifies pattern to apply rules to
 Functions similar to criteria
 <xsl:apply-templates> applies the rules
defined for a particular element
◦ Select attribute specifies elements to apply to

10.  <xsl:value-of> returns the value of a
specified node, function
◦ Select attribute specifies value source
 <xsl:copy> copies a node to the result tree
without any child nodes or attributes
 <xsl:copy-of> copies a node and
child/attribute nodes
 <xsl:output> controls the result tree
◦ method=“xml|html|text”

11.  <xsl:if> provides a boolean test to determine
processing
 <xsl:choose> offers an IF ... THEN ... ELSE
construct
 <xsl:for-each> allows each node in a group
to be processed
 <xsl:sort> specifies order for a group of
nodes

12.  Match can use
◦ node name
◦ current position (represented by “.”)
◦ relative position (for example, parent = “..”)
 Specifies where the transformation to be
applied