应用 SAX 方式解析 XML

分为三部分：

1、

package com;


import java.io.IOException;


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


import org.xml.sax.SAXException;


import com.ii.SAXParserHandler;
import com.jj.Book;


public class SAXTest {


public static void main(String[] args) {
// TODO Auto-generated method stub

//获取一个SAXParseFactory的实例
SAXParserFactory factory = SAXParserFactory.newInstance();

//通过factory获取SAXParser
try {
SAXParser parser = factory.newSAXParser();

//创建factory获取SAXParser实例
SAXParserHandler handler = new SAXParserHandler();
parser.parse("books.xml", handler);
System.out.println("~~~~! 共有: " + handler.getBookList().size() + "本书");
for (Book book : handler.getBookList()) {
System.out.println(book.getId());
System.out.println(book.getName());
System.out.println(book.getAuthor());
System.out.println(book.getYear());
System.out.println(book.getPrice());
System.out.println(book.getLanguage());
System.out.println("-----------finish---------");

}
} catch (ParserConfigurationException | SAXException e) {
// TODO Auto-generated catch block
e.printStackTrace();

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}


}


}

2、

package com.ii;


import java.util.ArrayList;


import javax.xml.stream.events.StartElement;


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


import com.jj.Book;


public class SAXParserHandler extends DefaultHandler {
String value = null;
Book book = null;
private ArrayList<Book> bookList = new ArrayList<Book>();

public ArrayList<Book> getBookList() {
return bookList;
}


int bookIndex = 0;
/*
* 用来遍历XML文件的开始标签
* 用来解析xml元素的
* */
@Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
// TODO Auto-generated method stub

//调用DefaultHandler类的startElement()方法;
super.startElement(uri, localName, qName, attributes);
//开始解析book元素的属性

if(qName.equals("book")){
//创建一个book对象
book = new Book();


bookIndex++;
//已知book元素下属性的名称，根据属性名称获取属性值
//String value = attributes.getValue("id");
//System.out.println("book的属性值是:" + value);
System.out.println("=====================开始遍历第" + bookIndex + "本书的内容=============================");
//在不知道book元素下属性的名称以及个数，如何获取属性名以及属性值
int num = attributes.getLength();
for(int i = 0; i < num; i++){

System.out.print("book元素的第: " + (i + 1) + "个属性名是: " + attributes.getQName(i));
System.out.println("----属性值是 : " + attributes.getValue(i));
if(attributes.getQName(i).equals("id")){
book.setId(attributes.getValue(i));

}
}
}
else if(!qName.equals("book") && !qName.equals("bookstore")){
System.out.print("节点名是 : " + qName);

}
}

/*
* 用来标识解析的开始
* */
@Override
public void startDocument() throws SAXException {
// TODO Auto-generated method stub
System.out.println("SAX解析开始！！");
super.startDocument();
}

/*
* 用来标识解析的结束
* */
@Override
public void endDocument() throws SAXException {
// TODO Auto-generated method stub
System.out.println("SAX解析结束！！");
super.endDocument();
}
/*
* 用来遍历XML文件的结束标签
* */
@Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
// TODO Auto-generated method stub
super.endElement(uri, localName, qName);
if(qName.equals("book")){
bookList.add(book);
book = null;
System.out.println("=====================结束遍历第" + bookIndex +"本书的内容=============================");
}
else if(qName.equals("name")){
book.setName(value);
}
else if(qName.equals("author")){
book.setAuthor(value);
}
else if(qName.equals("year")){
book.setYear(value);
}else if(qName.equals("price")){
book.setPrice(value);
}else if(qName.equals("language")){
book.setLanguage(value);
}
}

@Override
public void characters(char[] ch, int start, int length)
throws SAXException {
// TODO Auto-generated method stub
super.characters(ch, start, length);

value = new String(ch, start, length);
if(!value.trim().equals("")){
System.out.println("--节点值是: " + value);
}


}
}

3、

package com.jj;


public class Book {
private String id;
private String name;
private String author;
private String year;
private String price;
private String language;


public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public String getYear() {
return year;
}
public void setYear(String year) {
this.year = year;
}
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
public String getLanguage() {
return language;
}
public void setLanguage(String language) {
this.language = language;
}

}