SAX解析XML实例

  SAX解析xml简单示例：
  解析students.xml，打印解析结果。
1、students.xml:

<?xml version="1.0" encoding="UTF-8"?>
<students>
	<student id="1" enable="true">
		<name>刘亦菲</name>
		<sex>女</sex>
		<age>26</age>
		<email>[e-mail]</email>
	</student>
	<student id="2" enable="false">
		<name>张伟</name>
		<sex>男</sex>
		<age>26</age>
		<email>[e-mail]</email>
	</student>
	<student id="3" enable="true">
		<name>朱小明</name>
		<sex>女</sex>
		<age>26</age>
		<email>[e-mail]</email>
	</student>
</students>

2、SAXParserProcessor: XML解析器，用于解析XML

 package com.mzh.parsexml;

import java.util.List;
import java.util.ArrayList;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

public class ParseXmlProcessor extends DefaultHandler{
	
	private Student stu;//目标实例
	private List<Student> stuList;//目标实例集合
	private String currTag;//当前解析的标签名
	/*开始解析xml*/
	public void startDocument() throws SAXException{
		stuList = new ArrayList();
		System.out.println("XML文档解析开始...");
	}
	/*结束解析XML*/
	public void endDocument() throws SAXException{
		System.out.println("XML文档解析完毕。");
	}
	public void startElement(String uri,String localName,String qName,Attributes attributes) 
			throws SAXException{
		currTag=qName;
		//如果开始解析<student>标签，则新建一个student实例：
		if("student".equals(qName)){
			stu = new Student();
		}
	}
	public void endElement(String uri,String localName,String qName) throws SAXException{
		//如果<student>标签解析完毕，则把解析出的student实例添加到student集合中：
		if("student".equals(qName)){
			stuList.add(stu);
			stu=null;
		}
		currTag=null;//每解析完一个标签，必须清空currTag
	}
	/*解析标签值*/
	public void characters(char[] chr,int start,int length) throws SAXException{
		String value=new String(chr,start,length);
		if(currTag!=null){
			if("name".equals(currTag)){
				stu.setName(value);
			}else if("age".equals(currTag)){
				stu.setAge(Integer.parseInt(value));
			}else if("sex".equals(currTag)){
				stu.setSex(value);
			}else if("email".equals(currTag)){
				stu.setEmail(value);
			}
		}
	}
	/*返回解析结果集合*/
	public List<Student> getStudents(){
		return stuList;
	}
}

3、Student:目标实体

package com.mzh.parsexml;

import java.io.Serializable;

public class Student implements Serializable{
	private static final long serialVersionUID = -9151482311773013799L;
	private String name;
	private String sex;
	private int age;
	private String email;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public String getEmail() {
		return email;
	}
	public void setEmail(String email) {
		this.email = email;
	}
}

4、TestParseXml:测试XML解析器

package com.mzh.parsexml;

import java.io.File;
import java.io.IOException;
import java.util.List;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.SAXException;

public class TestParseXml {
	/*测试parseXml*/
	public static void main(String[] args) {
		String fileName="d:\\students.xml";
		//sax解析器工厂：
		SAXParserFactory parserFactory = SAXParserFactory.newInstance();
		ParseXmlProcessor parseXmlProcessor = new ParseXmlProcessor();
		try {
			//从sax解析器工厂中获取一个sax解析器：
			SAXParser parser=parserFactory.newSAXParser();
			//执行XML解析：
			parser.parse(new File(fileName),parseXmlProcessor);
			//输出XML解析结果：
			List<Student> students = parseXmlProcessor.getStudents();
			System.out.println("解析结果："+students.size()+"个学生：");
			for(Student stud:students){
				System.out.println("name："+stud.getName()+" " +
								   "age:"+stud.getAge()+" " +
								   "sex:"+stud.getSex()+" " +
								   "email:"+stud.getEmail());
			}
		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		} catch (SAXException e) {
			e.printStackTrace();
		}catch (IOException e) {
			e.printStackTrace();
		}
		
	}

}