进入黑马day2-解析xml三种方法（2）sax解析器解析

package cn.itheima.sax;

import java.util.ArrayList;

import java.util.List;

import javax.xml.parsers.SAXParser;

import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;

import org.xml.sax.SAXException;

import org.xml.sax.XMLReader;

import org.xml.sax.helpers.DefaultHandler;

public class Demo1 {

publicstatic void main(String[] args) throws Exception {

//获取解析器工厂

SAXParserFactoryfactory = SAXParserFactory.newInstance();

//获取解析器

SAXParserparser = factory.newSAXParser();

//获取读取器

XMLReaderread = parser.getXMLReader();

//注册监听器

MyContentHandler2handler = new MyContentHandler2();

read.setContentHandler(handler);

//读取xml

read.parse("book.xml");

//System.out.println(handler.getList().size());

}

}

class MyContentHandler2 extendsDefaultHandler{

//获取第一本书书名

booleanisBook = false;

intcount = 0;

@Override//获取到开始标签

publicvoid startElement(String uri, String localName, String name,

Attributesatts) throws SAXException {

if("书名".equals(name)){

count++;

if(count==1){

isBook= true;

}

}

}

@Override//获取到标签内容

publicvoid characters(char[] ch, int start, int length)

throws SAXException {

if(isBook==true){

System.out.println(newString(ch,start,length));

}

}

@Override//获取到结束标签

publicvoid endElement(String uri, String localName, String name)

throwsSAXException {

isBook= false;

}

}

// 获取第二本书的第一个属性

class MyContentHandler1 extendsDefaultHandler {

intcount = 0;//定义一个计数器

@Override

publicvoid startElement(String uri, String localName, String name,

Attributesatts) throws SAXException {

//获取第二本书的第一个属性

if("书".equals(name)){

count++;

if(count == 1) {

//获取所有属性时，要用getLength()方法判断属性长度

for(int x = 0; x < atts.getLength(); x++) {

StringattName = atts.getQName(0);

StringattValue = atts.getValue(0);

System.out.println(attName+ ":" + attValue);

}

//获取第二本书的第一个属性

StringattName = atts.getQName(0);

StringattValue = atts.getValue(0);

System.out.println(attName+ ":" + attValue);

}

}

}

}

//将xml中的数据读到Book对象中去

class MyContentHandler extendsDefaultHandler {

ListbookList = new ArrayList();

Stringele = null;

Bookbook = null;

@Override

publicvoid startElement(String uri, String localName, String name,

Attributesatts) throws SAXException {

if("书".equals(name)){

book= new Book();

bookList.add(book);

if(atts.getValue("出版社") != null) {

book.setPublish(atts.getValue("出版社"));

}

}

if("书名".equals(name)){

ele= "书名";

}

if("作者".equals(name)){

ele= "作者";

}

if("售价".equals(name)){

ele= "售价";

}

}

publicList getList() {

returnbookList;

}

@Override

publicvoid characters(char[] ch, int start, int length)

throwsSAXException {

if("书名".equals(ele)){

Stringname = new String(ch, start, length);

book.setName(name);

}

if("作者".equals(ele)){

Stringauth = new String(ch, start, length);

book.setName(auth);

}

if("售价".equals(ele)){

Stringprice = new String(ch, start, length);

book.setName(price);

}

}

@Override

publicvoid endElement(String uri, String localName, String name)

throwsSAXException {

ele= "";

}

}

附：book.xml文件，缺Book.java文件

<?xml version="1.0"encoding="gb2312"?>

<书架>

<书 出版社="人民出版社">

<书名>Java就业培训教程</书名>

<特价>10.0元</特价>

<作者>张孝祥</作者>

<售价>39.00元</售价>

</书>

<书>

<书名>JavaScript网页开发</书名>

<作者>张孝祥</作者>

<售价>28.00元</售价>

</书>

</书架>