SAX解析器使用回调函数（org.xml.sax.helpers.DefaultHandler）通知客户端XML文档结构。 您应该扩展DefaultHandler并重写一些方法来实现xml解析。

覆盖的方法是

• startDocument（）和endDocument（）–在XML文档的开头和结尾处调用的方法。
• startElement（）和endElement（）–在文档元素的开头和结尾处调用的方法。
• character（）–以XML文档元素的开始和结束标记之间的文本内容调用的方法。

下面的示例演示使用DefaultHandler解析和XML文档。 它执行xml到模型类的映射并生成对象列表。

XML文档样本：

<?xml version="1.0" encoding="UTF-8"?>
<catalog><book id="001" lang="ENG"><isbn>23-34-42-3</isbn><regDate>1990-05-24</regDate><title>Operating Systems</title><publisher country="USA">Pearson</publisher><price>400</price><authors><author>Ganesh Tiwari</author></authors></book><book id="002"><isbn>24-300-042-3</isbn><regDate>1995-05-12</regDate><title>Distributed Systems</title><publisher country="Nepal">Ekata</publisher><price>500</price><authors><author>Mahesh Poudel</author><author>Bikram Adhikari</author><author>Ramesh Poudel</author></authors></book>
</catalog>

Book对象的模型类，用于将xml映射到对象

/*** Book class stores book information, after parsing the xml* @author Ganesh Tiwari*/
public class Book {String lang;String title;String id;String isbn;Date regDate;String publisher;int price;List<String> authors;public Book(){authors=new ArrayList<String>();}//getters and setters
}

XML解析（Sax）的Java代码：

import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
public class MySaxParser extends DefaultHandler {List<Book> bookL;String bookXmlFileName;String tmpValue;Book bookTmp;SimpleDateFormat sdf= new SimpleDateFormat("yy-MM-dd");public MySaxParser(String bookXmlFileName) {this.bookXmlFileName = bookXmlFileName;bookL = new ArrayList<Book>();parseDocument();printDatas();}private void parseDocument() {// parseSAXParserFactory factory = SAXParserFactory.newInstance();try {SAXParser parser = factory.newSAXParser();parser.parse(bookXmlFileName, this);} catch (ParserConfigurationException e) {System.out.println("ParserConfig error");} catch (SAXException e) {System.out.println("SAXException : xml not well formed");} catch (IOException e) {System.out.println("IO error");}}private void printDatas() {// System.out.println(bookL.size());for (Book tmpB : bookL) {System.out.println(tmpB.toString());}}@Overridepublic void startElement(String s, String s1, String elementName, Attributes attributes) throws SAXException {// if current element is book , create new book// clear tmpValue on start of elementif (elementName.equalsIgnoreCase("book")) {bookTmp = new Book();bookTmp.setId(attributes.getValue("id"));bookTmp.setLang(attributes.getValue("lang"));}// if current element is publisherif (elementName.equalsIgnoreCase("publisher")) {bookTmp.setPublisher(attributes.getValue("country"));}}@Overridepublic void endElement(String s, String s1, String element) throws SAXException {// if end of book element add to listif (element.equals("book")) {bookL.add(bookTmp);}if (element.equalsIgnoreCase("isbn")) {bookTmp.setIsbn(tmpValue);}if (element.equalsIgnoreCase("title")) {bookTmp.setTitle(tmpValue);}if(element.equalsIgnoreCase("author")){bookTmp.getAuthors().add(tmpValue);}if(element.equalsIgnoreCase("price")){bookTmp.setPrice(Integer.parseInt(tmpValue));}if(element.equalsIgnoreCase("regDate")){try {bookTmp.setRegDate(sdf.parse(tmpValue));} catch (ParseException e) {System.out.println("date parsing error");}}}@Overridepublic void characters(char[] ac, int i, int j) throws SAXException {tmpValue = new String(ac, i, j);}public static void main(String[] args) {new MySaxParser("catalog.xml");}
}

解析输出：

Book [lang=ENG, title=Operating Systems, id=001, isbn=23-34-42-3, regDate=Thu May 24 00:00:00 NPT 1990, publisher=USA, price=400, authors=[Ganesh Tiwari]]
Book [lang=null, title=Distributed Systems, id=002, isbn=24-300-042-3, regDate=Fri May 12 00:00:00 NPT 1995, publisher=Nepal, price=500, authors=[Mahesh Poudel, Bikram Adhikari, Ramesh Poudel]]

参考：在GT's Blog上， 使用我们的JCG合作伙伴 Ganesh Tiwari 提供的完整代码 ， 使用SaxParser进行XML解析 。