闲来无事，看如何用DOM解析XML

//在下纯给自己做笔记，抱歉。
<?xml version="1.0" encoding="UTF-8"?>
<!--
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<bookstore>
    <book id="1">
        <name><a>aa</a>冰与火之歌</name>
        <author>乔治马丁</author>
        <year>2014</year>
        <price>89</price>
    </book>
    <book id="2">
        <name>安徒生童话</name>
        <year>2004</year>
        <price>77</price>
        <language>English</language>
    </book>

</bookstore>
    

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package domtest;

import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
 *
 * @author Administrator
 */
public class DomTest {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws ParserConfigurationException, SAXException, IOException {
        // TODO code application logic here
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        DocumentBuilder db=dbf.newDocumentBuilder();
        Document document=db.parse("newXMLDocument.xml");
        //获取所有book节点的集合
        NodeList bookList=document.getElementsByTagName("book");
        System.out.println(bookList.getLength());
        //遍历每一个book节点
        for(int i=0;i<bookList.getLength();i++){
            System.out.println("下面开始遍历第"+(i+1)+"本书的内容");
            //通过获取一个book节点
            Node book=bookList.item(i);
            //获取book节点的所有属性的集合
            NamedNodeMap attrs=book.getAttributes();
            System.out.println("第"+(i+1)+"本书共有"+attrs.getLength()+"个属性");
            for(int j=0;j<attrs.getLength();j++){
                //通过item()方法获取某一个属性
                Node attr=attrs.item(j);
                //获取属性名
                System.out.println("属性名："+attr.getNodeName());
                //获取属性值
                System.out.println("属性值："+attr.getNodeValue());
            }
            /*Element book=(Element)bookList.item(i);
            String attrValue=book.getAttribute("id");
            System.out.println("id属性的属性值为："+attrValue);*/
            NodeList childNodes=book.getChildNodes();
            //遍历childNodes获取每个节点的节点名和节点值
            System.out.println("第"+(i+1)+"本书共有"+childNodes.getLength()+"个子节点");
            for(int k=0;k<childNodes.getLength();k++){
                //区分出text类型的node以及element类型的node
                if(childNodes.item(k).getNodeType()==Node.ELEMENT_NODE){
                     System.out.println("第"+(k+1)+"个节点名："+childNodes.item(k).getNodeName());
                     System.out.println("第"+(k+1)+"个节点的节点值："+childNodes.item(k).getTextContent());
                }
               
            }
            System.out.println("======================结束遍历第"+(i+1)+"本书==========================");
        }
    }
    
}