Technologies for Grids and eBusiness XML 30'10'07

1
Technologies for Grids and eBusinessXML30.10.
07

• Dr. Ramin YahyapourComputer Engineering
  InstituteUniversity Dortmund

2
XML Example

• lt?xml version"1.0"?gt
• ltbooklistgt
• ltbook available"yes"gt
• lttitlegt Java and XML lt/titlegt
• ltauthorgt Brett McLaughlin lt/authorgt
• ltisbngt 3-89721-280-3 lt/isbngt
• lt/bookgt
• ltbook available"yes"gt
• lttitlegt Java 2 Micro Edition lt/titlegt
• ltauthorgt Eric Giguere lt/authorgt
• ltisbngt 0-471-39065-8 lt/isbngt
• lt/bookgt
• ltbook available"no"gt
• lttitlegt Core Jini lt/titlegt
• ltauthorgt W. Keith Edwards lt/authorgt
• ltisbngt 3-8272-9592-0 lt/isbngt
• lt/bookgt
• lt/booklistgt

3
SAX Parser (1)Import SAX Classes

• import org.xml.sax.Attributes
• import org.xml.sax.ContentHandler
• import org.xml.sax.Locator
• import org.xml.sax.SAXException
• import org.xml.sax.XMLReader
• import org.apache.xerces.parsers.SAXParser

4
SAX Parser (2)Install Parser and Input Stream

• public class MySAXParser
• public void parseFile(String uri)
• public static void main(String args)
• MySAXParser mySAX new MySAXParser()
• mySAX.parseFile("booklist.xml")

5
SAX Parser (3)Install ContentHandler and
Exceptions

• public void parseFile(String uri)
• XMLReader parser new SAXParser()
• // Create an instance of MyContentHandler
• ContentHandler myHandler new
  MyContentHandler()
• parser.setContentHandler(myHandler)
• try
• parser.parse(uri)
• catch (IOException e)
• System.out.println("Error reading
  file " e.getMessage())
• System.exit(1)
• catch (SAXException e)
• System.out.println("Error parsing
  file " e.getMessage())
• System.exit(1)
• System.out.println("File parsed
  successfully!")

6
SAX Parser (4)ContentHandler

• class MyContentHandler implements ContentHandler
  
• private Locator locator
• public void setDocumentLocator(Locator
  locator)
• public void startDocument() throws
  SAXException
• public void endDocument() throws
  SAXException
• public void startPrefixMapping(String
  prefix, String uri)
• public void endPrefixMapping(String
  prefix)
• throws SAXException

7
SAX Parser (5) ContentHandler

• class MyContentHandler implements ContentHandler
  
• public void startElement(
• String namespaceURI,
• String localName,
• String qName,
• Attributes atts)
• throws SAXException
• public void endElement(
• String namespaceURI,
• String localName,
• String qName)
• throws SAXException

8
SAX Parser (6) ContentHandler

• class MyContentHandler implements ContentHandler
  
• public void characters(char ch, int
  start,
• int length)
• public void ignorableWhitespace(char
  ch,
• int start,
• int length)
• throws SAXException
• public void processingInstruction(String
  target,
• String data)
• throws SAXException
• public void skippedEntity(String name)
• throws SAXException

9
ValidationExample DTD

• lt!ELEMENT Book ( Title,
• Author,
• ISBN)gt
• lt!ATTLIST Book
• available CDATA REQUIRED
• gt
• lt!ELEMENT Title (PCDATA)gt
• lt!ELEMENT Author (PCDATA)gt
• lt!ELEMENT ISBN (PCDATA)gt

10
ValidationExample XML Schema

• lt?xml version"1.0"?gt
• ltschema targetNamespace"http//www.oreilly.com/ca
  talog/javaxml/"gt
• ltelement name"Book" type"BookType" /gt
• ltcomplexType name"BookType"gt
• ltelement nameTitle" type"string" /gt
• ltelement nameAuthor" typestring" /gt
• ltelement nameISBN" type"string" /gt
• ltattribute nameavailable" defaultyes"gt
• ltsimpleType base"string"gtlt/simpleTypegt
• lt/attributegt
• lt/complexTypegt
• lt/schemagt

11
XML Document Tree
Book
XHTML
Price
ISBN
Content
HEAD
BODY
Title
Author
Chapter
Title
Chapter
Transforming Document Trees
12
Transformations with XSL

• lt?xml version"1.0"?gt
• ltxslstylesheet version"1.0"
  xmlnsxsl"http//www.w3.org/1999/XSL/Transform"
• gt
• Rules
• lt/xslstylesheetgt

13
Transformations with XSLRules

• lt?xml version"1.0"?gt
• ltxslstylesheet version"1.0"
  xmlnsxsl"http//www.w3.org/1999/XSL/Transform"
• gt
• ltxsltemplate matchBook"gt
• Action
• lt/xsltemplategt
• lt/xslstylesheetgt

14
Transformations with XSLExample of Transformation

• lt?xml version"1.0"?gt
• ltxslstylesheet version"1.0"
  xmlnsxsl"http//www.w3.org/1999/XSL/Transform"
• gt
• ltxsltemplate matchBook"gt
• lthtmlgt
• ltheadgt
• lttitlegt ltxslvalue-of select"title"/gt
  lt/titlegt
• lt/headgt
• ltbodygt
• ltxslapply-templates select" /gt
• lt/bodygt
• lt/htmlgt
• lt/xsltemplategt
• lt/xslstylesheetgt

XPath-Referencing
XPath-Filtering
15
Transformations with XSLIterations

• ltxsltemplate matchBook"gt
• ltxslfor-each selectChapter"gt
• ltligt
• ltxslvalue-of selectChapterName" /gt
• lt/ligt
• lt/xslfor-eachgt
• lt/xsltemplategt

16
Using DOM

• public class DOMParserDemo
• public void performDemo(String uri)
• System.out.println("Parsing XML File "
  uri "\n\n")
• // Instantiate your vendor's DOM parser
  implementation
• DOMParser parser new DOMParser()
• parser.setFeature("http//xml.org/sax/feat
  ures/validation", true)
• parser.parse(uri)
• Document doc parser.getDocument()
• do something with DOM
• public static void main(String args)

17
Using DOM (2)Example for Accessing DOM Nodes

• public void printNode(Node node, String indent)
  
• switch (node.getNodeType())
• case Node.DOCUMENT_NODE
• System.out.println("ltxml
  version\"1.0\"gt\n")
• // recurse on each child
• NodeList nodes
  node.getChildNodes()
• if (nodes ! null)
• for (int i0
  iltnodes.getLength() i)
• printNode(nodes.item(i),
  "")
• break
• case Node.ELEMENT_NODE
• case Node.TEXT_NODE
• case Node.CDATA_SECTION_NODE
• case Node.PROCESSING_INSTRUCTION_NODE
  
• case Node.ENTITY_REFERENCE_NODE
• case Node.DOCUMENT_TYPE_NODE

18
Using DOM (2)Example for Accessing DOM Nodes

• public void printNode(Node node, String indent)
  
• switch (node.getNodeType())
• case Node.DOCUMENT_NODE
• case Node.ELEMENT_NODE
• String name node.getNodeName()
• System.out.print(indent "lt"
  name)
• NamedNodeMap attributes
  node.getAttributes()
• for (int i0 iltattributes.getLeng
  th() i)
• Node current
  attributes.item(i)
• System.out.print(" "
  current.getNodeName()
• "\""
  current.getNodeValue()
• "\"")
• System.out.println("gt")
• // recurse on each child
• NodeList children
  node.getChildNodes()
• if (children ! null)
• for (int i0
  iltchildren.getLength() i)