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import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.io.SAXReader;public class Foo { public Document parse(URL url) throws DocumentException { SAXReader reader = new SAXReader(); Document document = reader.read(url); return document; }} document可以通过几个返回Java标准迭代器的方法实现遍历：
public void bar(Document document) throws DocumentException { Element root = document.getRootElement(); // iterate through child elements of root for ( Iterator i = root.elementIterator(); i.hasNext(); ) { Element element = (Element) i.next(); // do something } // iterate through child elements of root with element name "foo" for ( Iterator i = root.elementIterator( "foo" ); i.hasNext(); ) { Element foo = (Element) i.next(); // do something } // iterate through attributes of root for ( Iterator i = root.attributeIterator(); i.hasNext(); ) { Attribute attribute = (Attribute) i.next(); // do something } } 快速遍历大文件：
public void treeWalk(Document document) { treeWalk( document.getRootElement() ); } public void treeWalk(Element element) { for ( int i = 0, size = element.nodeCount(); i < size; i++ ) { Node node = element.node(i); if ( node instanceof Element ) { treeWalk( (Element) node ); } else { // do something.... } } } import org.dom4j.Document;import org.dom4j.DocumentHelper;import org.dom4j.Element;public class Foo { public Document createDocument() { Document document = DocumentHelper.createDocument(); Element root = document.addElement( "root" ); Element author1 = root.addElement( "author" ) .addAttribute( "name", "James" ) .addAttribute( "location", "UK" ) .addText( "James Strachan" ); Element author2 = root.addElement( "author" ) .addAttribute( "name", "Bob" ) .addAttribute( "location", "US" ) .addText( "Bob McWhirter" ); return document; }} 一种快速而且简单的方式如下：
FileWriter out = new FileWriter( "foo.xml" );document.write( out );
如果想要修改输出的格式，如智能缩进输出或者紧凑输出，或者你想要使用writer对象或者OutputStream对象来完成其他任务，则可以使用XMLWriter类。
import org.dom4j.Document;import org.dom4j.io.OutputFormat;import org.dom4j.io.XMLWriter;public class Foo { public void write(Document document) throws IOException { // lets write to a file XMLWriter writer = new XMLWriter( new FileWriter( "output.xml" ) ); writer.write( document ); writer.close(); // Pretty print the document to System.out OutputFormat format = OutputFormat.createPrettyPrint(); writer = new XMLWriter( System.out, format ); writer.write( document ); // Compact format to System.out format = OutputFormat.createCompactFormat(); writer = new XMLWriter( System.out, format ); writer.write( document ); }} 如果有到Document或者其他结点如Attribute、Element等的引用，则可以用asXML()方法将其转化为默认的XML文本。
Document document = ...;String text = document.asXML();
如果有String形式的XML，则可以使用DocumentHelper.parseText()将其转化为Document。
String text = "";Document document = DocumentHelper.parseText(text); James
其他操作
1 取得某结点下的某个子节点或属性
Element root = document.getRootElement();Element elem = root.element("book");Attribute attribute = root.attribute("id"); 2 取得属性的内容
String text = attribute.getText();
3 删除某属性
Attribute attribute=root.attribute("id"); root.remove(attribute); package test;import java.io.*;import java.util.Iterator;import java.util.List;import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.DocumentHelper;import org.dom4j.Element;import org.dom4j.io.OutputFormat;import org.dom4j.io.SAXReader;import org.dom4j.io.XMLWriter;import org.dom4j.Attribute;class XMLHelper { /** * 解析XML * @param filename 要解析的XML的文件名 */ public static void resolveXML(String filename) { try { SAXReader reader = new SAXReader(); Document document = reader.read(new File(filename)); Element root = document.getRootElement(); System.out.println("Root: " + root.getName()); for (Iterator it = root.elementIterator(); it.hasNext(); ) { Element e = (Element)it.next(); System.out.print(e.getName()); //遍历属性 for (Iterator it1 = e.attributeIterator(); it1.hasNext(); ) { Attribute attribute = (Attribute)it1.next(); System.out.println("[" + attribute.getName() + ": " + attribute.getText() + "]"); } //遍历子节点 for (Iterator it2 = e.elementIterator(); it2.hasNext(); ) { Element ee = (Element)it2.next(); System.out.println(" " + ee.getName() + ": " + ee.getText() + " "); } } } catch (Exception ex) { ex.printStackTrace(); } } public static Document createDocument() { Document document = DocumentHelper.createDocument(); Element root = document.addElement("bookstore"); //add book Element book = root.addElement("book") .addAttribute("category", "COOKING"); book.addElement("title") .addText("Everyday Italian"); book.addElement("author") .addText("Giada De Laurentiis"); book.addElement("year") .addText("2005"); book.addElement("price") .addText("30.00"); //add book book = root.addElement("book") .addAttribute("category", "CHILDREN"); book.addElement("title") .addText("Harry Potter"); book.addElement("author") .addText("J K. Rowling"); book.addElement("year") .addText("2005"); book.addElement("price") .addText("29.99"); return document; } /** * 生成XML文件 * @param filename 将生成的XML输出到该文件 */ public static void write(String filename) { Document document = createDocument(); try { //write to a file OutputFormat f=OutputFormat.createPrettyPrint(); XMLWriter writer = new XMLWriter(new FileWriter(filename), f); writer.write(document); writer.close(); //Pretty print the document to System.out /*OutputFormat format = OutputFormat.createPrettyPrint(); writer = new XMLWriter(System.out, format); writer.write(document);*/ //Compact print the document to System.out /*format = OutputFormat.createCompactFormat(); writer = new XMLWriter(System.out, format); writer.write(document);*/ } catch (Exception ex) { ex.printStackTrace(); } }}public class Main { public static void main(String[] args) throws Exception{ String filename = "E:\\Eclipse Project\\WebTest\\WebContent\\myxml.xml"; XMLHelper.resolveXML(filename); filename = "E:\\Eclipse Project\\WebTest\\WebContent\\myxml2.xml"; XMLHelper.write(filename); }} 转载：http://blog.csdn.net/foreverling/article/details/50152241