DOM

将XML文档换成一个对象模型的集合（DOM树），应用程序通过对模型的操作完成对XML数据的操作

File xmlfile=new File("D:/MyEclipse 10/test/WebRoot/NewFile.xml");
DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance();
DocumentBuilder builder=null;
try{
    builder=factory.newDocumentBuilder();
}catch(ParserConfigurationException e){
    e.printStackTrace();
}
org.w3c.dom.Document doc=null;
if(builder!=null){
    try{
        doc=builder.parse(xmlfile);
    }catch(SAXException e){
        e.printStackTrace();
    }catch(IOException e){
        e.printStackTrace();
    }
}
if(doc!=null){
    NodeList nl=doc.getElementsByTagName("name");
    System.out.println(nl.item(0).getFirstChild().getNodeValue());
}

SAX

按顺序访问

package tets;

import java.io.File;
import java.io.IOException;

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 ReadXMLBySAX {
    public static void main(String[] args) {
        File xmlfile = new File("D:/MyEclipse 10/test/WebRoot/NewFile.xml");
        SAXParserFactory factory = SAXParserFactory.newInstance();
        SAXParser paser;
        try {
            paser = factory.newSAXParser();
            paser.parse(xmlfile,new SAX());
        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        } catch (SAXException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

class SAX extends DefaultHandler {

    @Override
    public void startDocument() throws SAXException {
        System.out.println("<?xml version="1.0" encoding="UTF-8"?>");
    }

    @Override
    public void endDocument() throws SAXException {
        System.out.println("n 文档读取结束");
    }

    @Override
    public void startElement(String uri,String localName,String name,Attributes attributes) throws SAXException {
        System.out.print("<" + name);
        if (attributes != null) {
            for (int i = 0; i < attributes.getLength(); i++) {
                System.out.print(" " + attributes.getQName(i) + "=""
                        + attributes.getValue(i) + """);
            }
        }
        System.out.print(">");
    }

    @Override
    public void endElement(String uri,String name)
            throws SAXException {
        System.out.print("</" + name + ">");
    }

    @Override
    public void characters(char[] ch,int start,int length)
            throws SAXException {
        System.out.print(new String(ch,start,length));
    }
}

hibernate和spring框架都是用DOM4J读取xml配置文件的，另外还有一个Java组件 JDOM=DOM的修改文件+SAX的读取快速