Dom4j 解析 XML文件

import java.io.File;
import java.io.FileWriter;
import java.util.Iterator;
import java.util.List;
import org.dom4j.Attribute;
import org.dom4j.Document;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

public class Dom4jDemo {

/** Creates a new instance of Dom4jDemo */
public Dom4jDemo() {
}
/**
*The method createXML
*建立一个XML文档,文档名由输入属性决定
filename 需建立的文件名
返回操作结果
*/
public boolean createXML(String fileName){
boolean isOk = false;
//建立document对象
Document doc = DocumentHelper.createDocument();
//建立XML文档的根books
Element books = doc.addElement("books");
books.addComment("This is a test for dom4j");//加入一行注释
Element book = books.addElement("book");//加入第一个book节点
book.addAttribute("show", "yes");//加入show属性内容
Element title = book.addElement("title");//加入title节点
title.setText("Dom4j Tutorials");//为title设置内容
/**加入第二个book节点*/
book = books.addElement("book");
book.addAttribute("show", "yes");
title = book.addElement("title");
title.setText("Lucene Studing");
/**加入第三个book节点*/
book = books.addElement("book");
book.addAttribute("show", "no");
title = book.addElement("title");
title.setText("Lucene in Action");
/**加入owner节点*/
Element owner = books.addElement("owner");
owner.setText("O'Reilly");
/**
*将doc中的内容写入xml文件中
**/
try{
FileWriter file = new FileWriter(new File(fileName));
XMLWriter writer = new XMLWriter(file);
writer.write(doc);
writer.close();
isOk = true;
}catch(Exception e){
e.printStackTrace();
}
return isOk;
}
/**
*the method modifigXML
*     如果book节点中show属性的内容为yes,则修改成no
*     把owner项内容改为Tshinghua，并添加date节点
*     若title内容为Dom4j Tutorials,则删除该节点
*/
public boolean modifigXML(String oldFileName,String newFileName){
boolean isOk = false;
try{
SAXReader reader = new SAXReader();
Document doc = reader.read(new File(oldFileName));
/**修改内容之一: 如果book节点中show属性的内容为yes,则修改成no*/
List list = doc.selectNodes(" /books/book/@show ");
Iterator iter = list.iterator();
while(iter.hasNext()){
Attribute attr = (Attribute)iter.next();
if(attr.getValue().equals("yes"))
attr.setValue("no");
}
/**
*修改内容之二: 把owner项内容改为Tshinghua
*并在owner节点中加入date节点,
* date节点的内容为2004-09-11,
* 还为date节点添加一个属性type
*/
list = doc.selectNodes("/books/owner");
iter = list.iterator();
if(iter.hasNext()){
Element owner = (Element)iter.next();
owner.setText("Tshinghua");
Element date = owner.addElement("date");
date.setText("2006-07-30");
date.addAttribute("type", "Gregorian calendar");
}
/**修改内容之三: 若title内容为Dom4j Tutorials,则删除该节点*/
list = doc.selectNodes("/books/book");
iter = list.iterator();
while(iter.hasNext()){
Element elem = (Element)iter.next();
Iterator iterElem = elem.elementIterator("title");
if(iterElem.hasNext()){
Element remTitle = (Element)iterElem.next();
if(remTitle.getText().trim().equals("Dom4j Tutorials"))
elem.remove(remTitle);
}
}
//将doc中的内容写入文件中
try{
FileWriter newFile = new FileWriter(new File(newFileName));
XMLWriter newWriter = new XMLWriter(newFile);
newWriter.write(doc);
newWriter.close();
}catch(Exception e){
e.printStackTrace();
}
isOk = true;
}catch(Exception e){
e.printStackTrace();
}
return isOk;
}
/**
*the method formatXML
*-------------------------
*默认的输出方式为紧凑方式，默认编码为UTF-8，
* 但对于我们的应用而言，一般都要用到中文，
* 并且希望显示时按自动缩进的方式的显示，这就需用到OutputFormat类。
*/
public boolean formatXML(String fileName){
boolean isOk = false;
try{
SAXReader reader = new SAXReader();
Document doc = reader.read(new File(fileName));
XMLWriter formatWriter = null;
/**
*格式化输出,类型IE浏览一样
*指定XML编码
*/
OutputFormat format = OutputFormat.createPrettyPrint();
format.setEncoding("gb2312");
formatWriter = new XMLWriter(new FileWriter(new File(fileName)), format);
formatWriter.write(doc);
formatWriter.close();

isOk = true;
}catch(Exception e){
e.printStackTrace();
}
return isOk;
}
/**
*the method readXML
*/
public void readXML(String fileName){
try{
SAXReader reader = new SAXReader();
Document doc = reader.read(new File(fileName));
List list = doc.selectNodes("/books/book");
Iterator iter = list.iterator();
while(iter.hasNext()){
Element book = (Element)iter.next();
Iterator title = book.elementIterator("title");
if(title.hasNext()){
Element elemTitle = (Element)title.next();
System.out.print("Title: "+elemTitle.getText());
System.out.print("   Show: "+book.attributeValue("show")+"\n");
}
}

list = doc.selectNodes("/books/owner");
iter = list.iterator();
if(iter.hasNext()){
Element owner = (Element)iter.next();
System.out.println("Owner: "+owner.getText());
System.out.println("Date: "+owner.elementText("date"));
}
}catch(Exception e){
e.printStackTrace();
}
}
/*
Title: Dom4j Tutorials   Show: yes
Title: Lucene Studing   Show: yes
Title: Lucene in Action   Show: no
Owner: O'Reilly
Date: null
*/
/**
*the method main
*/
public static void main(String[] args){
long start = System.currentTimeMillis();//开始计时
Dom4jDemo dom4jDemo = new Dom4jDemo();
String fileName = "dom4jDemo.xml";
String newFileName = "new_dom4jDemo.xml";
System.out.println(fileName+"正在创建中...");
boolean isOk_create = dom4jDemo.createXML(fileName);
if(isOk_create) System.out.println(fileName+"创建成功!");
else System.out.println("创建失败!请检查后重新再试!");

System.out.println("正在更新中...");
boolean isOk_modi = dom4jDemo.modifigXML(fileName, newFileName);
if(isOk_modi) System.out.println("恭喜,更新完成!");
else System.out.println("更新失败!请检查后重新再试!");

System.out.println("正在格式化中...");
boolean isOk_format = dom4jDemo.formatXML(fileName);
if(isOk_format) System.out.println("恭喜,格式化完成!");
else System.out.println("格式化失败!请检查后重新再试!");

System.out.println("正在读取文件 "+fileName+" ...");
System.out.println("------------------------------------------------");
dom4jDemo.readXML(fileName);
System.out.println("------------------------------------------------");
System.out.println(fileName+"读取成功!");
System.out.println("正在读取文件 "+newFileName+" ...");
System.out.println("------------------------------------------------");
dom4jDemo.readXML(newFileName);
System.out.println("------------------------------------------------");
System.out.println(fileName+"读取成功!");
System.out.println("一共耗时： "+(System.currentTimeMillis()-start)+"毫秒!");
}
}