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📄 Contents

  1. Sams Teach Yourself XML in 21 Days, Third Edition
  2. Table of Contents
  3. About the Author
  4. Acknowledgments
  5. We Want to Hear from You!
  6. Introduction
  7. Part I: At a Glance
  8. Day 1. Welcome to XML
  9. All About Markup Languages
  10. All About XML
  11. Looking at XML in a Browser
  12. Working with XML Data Yourself
  13. Structuring Your Data
  14. Creating Well-Formed XML Documents
  15. Creating Valid XML Documents
  16. How XML Is Used in the Real World
  17. Online XML Resources
  18. Summary
  19. Q&A
  20. Workshop
  21. Day 2. Creating XML Documents
  22. Choosing an XML Editor
  23. Using XML Browsers
  24. Using XML Validators
  25. Creating XML Documents Piece by Piece
  26. Creating Prologs
  27. Creating an XML Declaration
  28. Creating XML Comments
  29. Creating Processing Instructions
  30. Creating Tags and Elements
  31. Creating CDATA Sections
  32. Handling Entities
  33. Summary
  34. Q&A
  35. Workshop
  36. Day 3. Creating Well-Formed XML Documents
  37. What Makes an XML Document Well-Formed?
  38. Creating an Example XML Document
  39. Understanding the Well-Formedness Constraints
  40. Using XML Namespaces
  41. Understanding XML Infosets
  42. Understanding Canonical XML
  43. Summary
  44. Q&A
  45. Workshop
  46. Day 4. Creating Valid XML Documents: DTDs
  47. All About DTDs
  48. Validating a Document by Using a DTD
  49. Creating Element Content Models
  50. Commenting a DTD
  51. Supporting External DTDs
  52. Handling Namespaces in DTDs
  53. Summary
  54. Q&A
  55. Workshop
  56. Declaring Attributes in DTDs
  57. Day 5. Handling Attributes and Entities in DTDs
  58. Specifying Default Values
  59. Specifying Attribute Types
  60. Handling Entities
  61. Summary
  62. Q&A
  63. Workshop
  64. Day 6. Creating Valid XML Documents: XML Schemas
  65. Using XML Schema Tools
  66. Creating XML Schemas
  67. Dissecting an XML Schema
  68. The Built-in XML Schema Elements
  69. Creating Elements and Types
  70. Specifying a Number of Elements
  71. Specifying Element Default Values
  72. Creating Attributes
  73. Summary
  74. Q&A
  75. Workshop
  76. Day 7. Creating Types in XML Schemas
  77. Restricting Simple Types by Using XML Schema Facets
  78. Creating XML Schema Choices
  79. Using Anonymous Type Definitions
  80. Declaring Empty Elements
  81. Declaring Mixed-Content Elements
  82. Grouping Elements Together
  83. Grouping Attributes Together
  84. Declaring all Groups
  85. Handling Namespaces in Schemas
  86. Annotating an XML Schema
  87. Summary
  88. Q&A
  89. Workshop
  90. Part I. In Review
  91. Well-Formed Documents
  92. Valid Documents
  93. Part II: At a Glance
  94. Day 8. Formatting XML by Using Cascading Style Sheets
  95. Our Sample XML Document
  96. Introducing CSS
  97. Connecting CSS Style Sheets and XML Documents
  98. Creating Style Sheet Selectors
  99. Using Inline Styles
  100. Creating Style Rule Specifications in Style Sheets
  101. Summary
  102. Q&A
  103. Workshop
  104. Day 9. Formatting XML by Using XSLT
  105. Introducing XSLT
  106. Transforming XML by Using XSLT
  107. Writing XSLT Style Sheets
  108. Using <xsl:apply-templates>
  109. Using <xsl:value-of> and <xsl:for-each>
  110. Matching Nodes by Using the match Attribute
  111. Working with the select Attribute and XPath
  112. Using <xsl:copy>
  113. Using <xsl:if>
  114. Using <xsl:choose>
  115. Specifying the Output Document Type
  116. Summary
  117. Q&A
  118. Workshop
  119. Day 10. Working with XSL Formatting Objects
  120. Introducing XSL-FO
  121. Using XSL-FO
  122. Using XSL Formatting Objects and Properties
  123. Building an XSL-FO Document
  124. Handling Inline Formatting
  125. Formatting Lists
  126. Formatting Tables
  127. Summary
  128. Q&A
  129. Workshop
  130. Part II. In Review
  131. Using CSS
  132. Using XSLT
  133. Using XSL-FO
  134. Part III: At a Glance
  135. Day 11. Extending HTML with XHTML
  136. Why XHTML?
  137. Writing XHTML Documents
  138. Validating XHTML Documents
  139. The Basic XHTML Elements
  140. Organizing Text
  141. Formatting Text
  142. Selecting Fonts: <font>
  143. Comments: <!-->
  144. Summary
  145. Q&A
  146. Workshop
  147. Day 12. Putting XHTML to Work
  148. Creating Hyperlinks: <a>
  149. Linking to Other Documents: <link>
  150. Handling Images: <img>
  151. Creating Frame Documents: <frameset>
  152. Creating Frames: <frame>
  153. Creating Embedded Style Sheets: <style>
  154. Formatting Tables: <table>
  155. Creating Table Rows: <tr>
  156. Formatting Table Headers: <th>
  157. Formatting Table Data: <td>
  158. Extending XHTML
  159. Summary
  160. Q&A
  161. Workshop
  162. Day 13. Creating Graphics and Multimedia: SVG and SMIL
  163. Introducing SVG
  164. Creating an SVG Document
  165. Creating Rectangles
  166. Adobe's SVG Viewer
  167. Using CSS Styles
  168. Creating Circles
  169. Creating Ellipses
  170. Creating Lines
  171. Creating Polylines
  172. Creating Polygons
  173. Creating Text
  174. Creating Gradients
  175. Creating Paths
  176. Creating Text Paths
  177. Creating Groups and Transformations
  178. Creating Animation
  179. Creating Links
  180. Creating Scripts
  181. Embedding SVG in HTML
  182. Introducing SMIL
  183. Summary
  184. Q&A
  185. Workshop
  186. Day 14. Handling XLinks, XPointers, and XForms
  187. Introducing XLinks
  188. Beyond Simple XLinks
  189. Introducing XPointers
  190. Introducing XBase
  191. Introducing XForms
  192. Summary
  193. Workshop
  194. Part III. In Review
  195. Part IV: At a Glance
  196. Day 15. Using JavaScript and XML
  197. Introducing the W3C DOM
  198. Introducing the DOM Objects
  199. Working with the XML DOM in JavaScript
  200. Searching for Elements by Name
  201. Reading Attribute Values
  202. Getting All XML Data from a Document
  203. Validating XML Documents by Using DTDs
  204. Summary
  205. Q&A
  206. Workshop
  207. Day 16. Using Java and .NET: DOM
  208. Using Java to Read XML Data
  209. Finding Elements by Name
  210. Creating an XML Browser by Using Java
  211. Navigating Through XML Documents
  212. Writing XML by Using Java
  213. Summary
  214. Q&A
  215. Workshop
  216. Day 17. Using Java and .NET: SAX
  217. An Overview of SAX
  218. Using SAX
  219. Using SAX to Find Elements by Name
  220. Creating an XML Browser by Using Java and SAX
  221. Navigating Through XML Documents by Using SAX
  222. Writing XML by Using Java and SAX
  223. Summary
  224. Q&A
  225. Workshop
  226. Day 18. Working with SOAP and RDF
  227. Introducing SOAP
  228. A SOAP Example in .NET
  229. A SOAP Example in Java
  230. Introducing RDF
  231. Summary
  232. Q&A
  233. Workshop
  234. Part IV. In Review
  235. Part V: At a Glance
  236. Day 19. Handling XML Data Binding
  237. Introducing DSOs
  238. Binding HTML Elements to HTML Data
  239. Binding HTML Elements to XML Data
  240. Binding HTML Tables to XML Data
  241. Accessing Individual Data Fields
  242. Binding HTML Elements to XML Data by Using the XML DSO
  243. Binding HTML Tables to XML Data by Using the XML DSO
  244. Searching XML Data by Using a DSO and JavaScript
  245. Handling Hierarchical XML Data
  246. Summary
  247. Q&A
  248. Workshop
  249. Day 20. Working with XML and Databases
  250. XML, Databases, and ASP
  251. Storing Databases as XML
  252. Using XPath with a Database
  253. Introducing XQuery
  254. Summary
  255. Q&A
  256. Workshop
  257. Day 21. Handling XML in .NET
  258. Creating and Editing an XML Document in .NET
  259. From XML to Databases and Back
  260. Reading and Writing XML in .NET Code
  261. Using XML Controls to Display Formatted XML
  262. Creating XML Web Services
  263. Summary
  264. Q&A
  265. Workshop
  266. Part V. In Review
  267. Appendix A. Quiz Answers
  268. Quiz Answers for Day 1
  269. Quiz Answers for Day 2
  270. Quiz Answers for Day 3
  271. Quiz Answers for Day 4
  272. Quiz Answers for Day 5
  273. Quiz Answers for Day 6
  274. Quiz Answers for Day 7
  275. Quiz Answers for Day 8
  276. Quiz Answers for Day 9
  277. Quiz Answers for Day 10
  278. Quiz Answers for Day 11
  279. Quiz Answers for Day 12
  280. Quiz Answers for Day 13
  281. Quiz Answers for Day 14
  282. Quiz Answers for Day 15
  283. Quiz Answers for Day 16
  284. Quiz Answers for Day 17
  285. Quiz Answers for Day 18
  286. Quiz Answers for Day 19
  287. Quiz Answers for Day 20
  288. Quiz Answers for Day 21
Recommended Book

Navigating Through XML Documents by Using SAX

Yesterday you used some W3C DOM methods (for example, getNextSibling, getPreviousSibling, getFirstChild, getLastChild, getParent) to navigate through an XML document. But you can't do that in SAX because a SAX parser does not create a tree of nodes to support these methods. Instead, you have to wait until what you are searching for comes to you. Yesterday you navigated through an XML document, looking for the last senator in an XML document. You can do the same in SAX; in this case, you just have to wait for the last senator to come to us.

Here's how it looks in code; in the startElement method, we count the number of senators we've seen, and if we're on the third and last senator, we set a Boolean variable, lastSenatorBoolean, to true:

public void startElement(String uri, String localName,
    String qualifiedName, Attributes attributes)
{
    if(qualifiedName.equals("senator")) {

           senatorNumber++;

       }


       if(senatorNumber == 3) {

           lastSenatorBoolean = true;

       }
    .
    .
    .

If you're inside the last <senator> element, you can catch the <firstName> and <lastName> elements by setting the Booleans firstNameBoolean and lastNameBoolean to true:

public void startElement(String uri, String localName,
    String qualifiedName, Attributes attributes)
{
    if(qualifiedName.equals("senator")) {
        senatorNumber++;
    }

    if(senatorNumber == 3) {
        lastSenatorBoolean = true;
    }

    if(qualifiedName.equals("firstName") && lastSenatorBoolean) {

           firstNameBoolean = true;

       }


       if(qualifiedName.equals("lastName")  && lastSenatorBoolean) {

           firstNameBoolean = false;

           lastNameBoolean = true;

       }
}

By using the firstNameBoolean and lastNameBoolean variables, you can catch the name of the last senator when you handle text nodes:

public void characters(char characters[], int start, int length)
{
    String characterData = (new String(characters, start, length)).trim();
    if(characterData.indexOf("\n") < 0 && characterData.length() > 0) {
        if(firstNameBoolean) {

               firstName = characterData;

           }

           if(lastNameBoolean) {

               lastName = characterData;

           }
    }
}

Now that you've stored the last senator's first and last names in the variables firstName and lastName, you can display them when in the endElement method:

public void endElement(String uri, String localName,
    String qualifiedName)
{
    if(lastSenatorBoolean && lastNameBoolean){

           System.out.println("Last senator: " + firstName +

               " " + lastName);

           lastSenatorBoolean = false;

           firstNameBoolean = false;

           lastNameBoolean = false;

       }
}

And that's it—when you run this application, you see this result:

%java ch17_06 ch17_01.xml
Last senator: Jay Jones

This code gives you the same results as when you used DOM methods yesterday, but instead of going to find the senator as you did yesterday, this time you used SAX methods and let the senator come to you. Listing 17.6 shows the full code for this application, ch17_06.java.

Example 17.6. Navigating XML by Using SAX (ch17_06.java)

import java.io.*;
import org.xml.sax.*;
import javax.xml.parsers.*;
import org.xml.sax.helpers.DefaultHandler;

public class ch17_06 extends DefaultHandler
{
    int senatorNumber;
    boolean lastSenatorBoolean = false, firstNameBoolean = false,
        lastNameBoolean = false;
    String firstName, lastName;

    public static void main(String args[])
    {
        ch17_06 obj = new ch17_06();
        obj.childLoop(args[0]);
    }

    public void childLoop(String uri)
    {
        DefaultHandler defaultHandler = this;
        SAXParserFactory factory = SAXParserFactory.newInstance();
        try {
            SAXParser saxParser = factory.newSAXParser();
            saxParser.parse(new File(uri), defaultHandler);
        } catch (Throwable t) {}
    }

    public void startElement(String uri, String localName,
        String qualifiedName, Attributes attributes)
    {
        if(qualifiedName.equals("senator")) {
            senatorNumber++;
        }

        if(senatorNumber == 3) {
            lastSenatorBoolean = true;
        }

        if(qualifiedName.equals("firstName") && lastSenatorBoolean) {
            firstNameBoolean = true;
        }

        if(qualifiedName.equals("lastName")  && lastSenatorBoolean) {
            firstNameBoolean = false;
            lastNameBoolean = true;
        }

    }

    public void characters(char characters[], int start, int length)
    {
        String characterData = (new String(characters, start, length)).trim();
        if(characterData.indexOf("\n") < 0 && characterData.length() > 0) {
            if(firstNameBoolean) {
                firstName = characterData;
            }
            if(lastNameBoolean) {
                lastName = characterData;
            }
        }
    }

    public void endElement(String uri, String localName,
        String qualifiedName)
    {
        if(lastSenatorBoolean && lastNameBoolean){
            System.out.println("Last senator: " + firstName +
                " " + lastName);
            lastSenatorBoolean = false;
            firstNameBoolean = false;
            lastNameBoolean = false;
        }
    }

    public void warning(SAXParseException exception)
    {
        System.err.println("Warning: " +
            exception.getMessage());
    }

    public void error(SAXParseException exception)
    {
        System.err.println("Error: " +
            exception.getMessage());
    }

    public void fatalError(SAXParseException exception)
    {
        System.err.println("Fatal error: " +
            exception.getMessage());
    }
}

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