Handouts from Web Services 1 (Dave Stampf)

DesignPatterns.xml

<?xml version="1.0" encoding="UTF-8"?>

<!--
    Document   : DesignPatterns.xml
    Created on : September 7, 2003, 12:52 PM
    Author     : Dave Stampf
    Description:
        Purpose of the document follows.
-->

<book isbn="0-201-633511-2">
    <title>Design Patterns</title>
    <subtitle>Elements of Reusable Object-Oriented Software</subtitle>
    <author>Eric Gamma</author>
    <author>Richard Helm</author>
    <author>Ralph Johnson</author>
    <author>John Vlissides</author>
    <publisher>Addison-Wesley Publishing Company</publisher>
    <copyright>1995</copyright>
    <hardcover />

</book>

DesignPatternsWithDTD.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book SYSTEM "c:/WebServicesTutorial/Book.dtd">
<!--
    Document   : DesignPatterns.xml
    Created on : September 7, 2003, 12:52 PM
    Author     : Dave Stampf
    Description:
        Purpose of the document follows.
-->

<book isbn="0-201-633511-2">
    <title>Design Patterns</title>
    <subtitle>Elements of Reusable Object-Oriented Software</subtitle>
    <author>Eric Gamma</author>
    <author>Richard Helm</author>
    <author>Ralph Johnson</author>
    <author>John Vlissides</author>
    <publisher>Addison-Wesley Publishing Company</publisher>
    <copyright>1995</copyright>
    <hardcover />

</book>

Book.dtd

<?xml version='1.0' encoding='UTF-8'?>

<!--
    An example how to use this DTD from your XML document:

    <?xml version="1.0"?>

    <!DOCTYPE book SYSTEM "Book.dtd">

    <book>
    ...
    </book>
-->

<!--- Put your DTDDoc comment here. -->
<!ELEMENT hardcover EMPTY>

<!--- Put your DTDDoc comment here. -->
<!ELEMENT copyright (#PCDATA)>

<!--- Put your DTDDoc comment here. -->
<!ELEMENT publisher (#PCDATA)>

<!--- Put your DTDDoc comment here. -->
<!ELEMENT author (#PCDATA)>

<!--- Put your DTDDoc comment here. -->
<!ELEMENT subtitle (#PCDATA)>

<!--- Put your DTDDoc comment here. -->
<!ELEMENT title (#PCDATA)>

<!--- Put your DTDDoc comment here. -->
<!ELEMENT book ( title, subtitle?, author+, publisher, copyright, hardcover? ) >
<!ATTLIST book
    isbn CDATA #IMPLIED
  >

Book.java

import java.io.*;
import javax.xml.parsers.*;
import org.xml.sax.InputSource;
import org.w3c.dom.*;

public class Book {
    
    public Book(Reader r) throws Exception {        
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        dbf.setValidating(true);
        DocumentBuilder db = dbf.newDocumentBuilder();
        System.out.println(db.getClass());
        InputSource is = new InputSource(r);
        
        Document doc = db.parse(is);
        process(doc);
    }
    
    private void process(Document doc) {
        System.out.println("Have the document");
        Node book = doc.getDocumentElement();
        
        // find the title, first author, publisher and copyright date
        
        String title=null, author = null, pub=null, copy=null;
        NodeList nl = book.getChildNodes();
        for (int i = 0; i < nl.getLength(); i++) {
            Node n = nl.item(i);
            String s = n.getNodeName();
            if (s.equals("title")) {
                title = n.getFirstChild().getNodeValue();
            } else if (s.equals("author")) {
                if (author == null) {
                    author = n.getFirstChild().getNodeValue();
                } else if (! author.endsWith(", et al")) {
                    author += ", et al";
                }
            } else if (s.equals("publisher")) {
                pub = n.getFirstChild().getNodeValue();
            } else if (s.equals("copyright")) {
                copy = n.getFirstChild().getNodeValue();
            }
        }
        System.out.println(title + " by " + author + " published by " + pub + 
            " in " + copy);
    }
    
    public static void main(String[] args) throws Exception{
        Reader r = new FileReader("C:/WebServicesTutorial/DesignPatternsWithDTD.xml");
        Book b = new Book(r);
    }
}

Shorten.java

import java.io.*;
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.*;
import javax.xml.transform.stream.*;
import org.xml.sax.InputSource;
import org.w3c.dom.*;

public class Shorten {
    
    public Shorten(Reader r) throws Exception {        
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        dbf.setValidating(true);
        DocumentBuilder db = dbf.newDocumentBuilder();
        InputSource is = new InputSource(r);
        
        Document doc = db.parse(is);
        process(doc);
    }
    
    private void process(Document doc) throws Exception {
        Node book = doc.getDocumentElement();
        
        int numAuthors = 0;
        
        NodeList nl = book.getChildNodes();
        for (int i = 0; i < nl.getLength(); i++) {
            Node n = nl.item(i);
            String s = n.getNodeName();
            if (s.equals("author")) {
                numAuthors++;
                if (numAuthors == 1) continue;
                else if (numAuthors == 2) {
                    n.getFirstChild().setNodeValue("et al");
                } else {
                    book.removeChild(n);
                }   
            }
        }
        
        // ok - output new XML - you've seen this pattern b4
        
        TransformerFactory tf = TransformerFactory.newInstance();
        Transformer t = tf.newTransformer();
        t.transform(new DOMSource(doc), new StreamResult(System.out));
    }
    
    public static void main(String[] args) throws Exception{
        Reader r = new FileReader("C:/WebServicesTutorial/DesignPatternsWithDTD.xml");
        Shorten b = new Shorten(r);
    }
}