Jdom操作、创建和解析XML

需要导入Jdom的一个jar包；

1、Jdom创建XML

package com.shengsiyuan.jdom;

import java.io.FileWriter;

import org.jdom.Attribute;

import org.jdom.Comment;

import org.jdom.Document;

import org.jdom.Element;

import org.jdom.output.Format;

import org.jdom.output.XMLOutputter;

public class JDomTest1

{

public static void main(String[] args) throws Exception

{

//创建文档

Document document = new Document();

//创建文档根元素

Element root = new Element("root");

//向文档呢添加根元素

document.addContent(root);

//添加注释

Comment comment = new Comment("This is my comments");

//在根元素下添加注释

root.addContent(comment);

//创建一个元素

Element e = new Element("hello");

//给元素添加属性的第一种方式,它有返回值，返回一个Element对象

e.setAttribute("sohu", "www.sohu.com");

//给根元素添加属性

root.addContent(e);

Element e2 = new Element("world");

//创建元素属性的第二种方式

Attribute attr = new Attribute("test", "hehe");

//给元素添加属性

e2.setAttribute(attr);

//将元素添加到根元素下

e.addContent(e2);

//添加元素属性和文本内容，属于方法链的编程风格

e2.addContent(new Element("aaa").setAttribute("a", "b")

.setAttribute("x", "y").setAttribute("gg", "hh").setText("text content"));

//设置其格式,一般还有一个没有缩进与空格的格式getRawFormat，主要用于XML的网络传输，因为它没有空格，减少网络传输的数据量。

Format format = Format.getPrettyFormat();

//设置元素前面空格

format.setIndent(" ");

//设置编码方式

// format.setEncoding("gbk");

//将XML文档输出

XMLOutputter out = new XMLOutputter(format);

out.output(document, new FileWriter("jdom.xml"));

}

}

2、Jdom解析XML

package com.shengsiyuan.jdom;

import java.io.File;

import java.io.FileOutputStream;

import java.util.List;

import org.jdom.Attribute;

import org.jdom.Document;

import org.jdom.Element;

import org.jdom.input.SAXBuilder;

import org.jdom.output.Format;

import org.jdom.output.XMLOutputter;

public class JDomTest2

{

public static void main(String[] args) throws Exception

{

//JDOM从XML中解析

SAXBuilder builder = new SAXBuilder();

//获得XML文档对象

Document doc = builder.build(new File("jdom.xml"));

//得到文档根元素

Element element = doc.getRootElement();

System.out.println(element.getName());

//得到根元素下的hello元素

Element hello = element.getChild("hello");

System.out.println(hello.getText());

//得到hello子元素下的属性

List list = hello.getAttributes();

//得到hello元素下属性的名字和值

for(int i = 0 ;i < list.size(); i++)

{

Attribute attr = (Attribute)list.get(i);

String attrName = attr.getName();

String attrValue = attr.getValue();

System.out.println(attrName + "=" + attrValue);

}

//删除hello下的world子元素

hello.removeChild("world");

//将文档保存到另一个文件

XMLOutputter out = new XMLOutputter(Format.getPrettyFormat().setIndent(" "));

out.output(doc, new FileOutputStream("jdom2.xml"));

}

}

3、综合实例

package cn.com.xmltest;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.util.List;

import org.jdom.Document;

import org.jdom.Element;

import org.jdom.JDOMException;

import org.jdom.input.SAXBuilder;

import org.jdom.output.Format;

import org.jdom.output.XMLOutputter;

public class XMLTest

{

public static void main(String[] args)

{

modifyXML();

}

public static void createXML()

{

Element root = new Element("学生信息");

Element stu1 = new Element("学生");

Element stu2 = new Element("学生");

Element name1 = new Element("姓名");

Element sex1 = new Element("性别");

Element age1 = new Element("年龄");

Element name2 = new Element("姓名");

Element sex2 = new Element("性别");

Element age2 = new Element("年龄");

name1.setText("小明");

sex1.setText("男");

age1.setText("19");

name2.setText("小花");

sex2.setText("女");

age2.setText("20");

root.addContent(stu1);

root.addContent(stu2);

stu1.addContent(name1);

stu1.addContent(sex1);

stu1.addContent(age1);

stu2.addContent(name2);

stu2.addContent(sex2);

stu2.addContent(age2);

Document doc = new Document(root);

Format f = Format.getPrettyFormat();

f.setEncoding("gb2312");

XMLOutputter out = new XMLOutputter(f);

try

{

out.output(doc, new FileOutputStream(new File("c:/myxml.xml")));

}

catch (FileNotFoundException e)

{

e.printStackTrace();

}

catch (IOException e)

{

e.printStackTrace();

}

}

public static void searchXML()

{

SAXBuilder build = new SAXBuilder();

try

{

Document doc = build.build("c:/myxml.xml");

Element e = doc.getRootElement();

List<Element> list = e.getChildren();

for (Element ele : list)

{

System.out.println(ele.getChild("姓名").getName() + ":"

+ ele.getChild("姓名").getText());

System.out.println(ele.getChild("性别").getName() + ":"

+ ele.getChild("性别").getText());

System.out.println(ele.getChild("年龄").getName() + ":"

+ ele.getChild("年龄").getText());

}

}

catch (JDOMException e)

{

e.printStackTrace();

}

catch (IOException e)

{

e.printStackTrace();

}

}

public static void addElement()

{

SAXBuilder build=new SAXBuilder();

try

{

Document doc=build.build("c:/myxml.xml");

Element root=doc.getRootElement();

Element stu=root.getChild("学生");

Element cla=new Element("班级");

cla.addContent("2班");

stu.addContent(cla);

XMLOutputter out=new XMLOutputter();

out.output(doc,new FileOutputStream(new File("c:/myxml.xml")));

}

catch (JDOMException e)

{

e.printStackTrace();

}

catch (IOException e)

{

e.printStackTrace();

}

}

public static void modifyXML()

{

SAXBuilder build=new SAXBuilder();

Document doc;

try

{

doc = build.build("c:/myxml.xml");

Element root=doc.getRootElement();

Element stu=root.getChild("学生");

Element age=stu.getChild("年龄2");

age.setName("年龄");

age.setText("10");

List<Element> list=stu.getChildren();

for(Element e:list)

{

if(e.getName().equals(""));

// {

//// Element height=new Element("身高");

//// height.setText("175厘米");

//// root.addContent(height);

// stu.removeChild(str);

// }

}

XMLOutputter out=new XMLOutputter();

out.output(doc,new FileOutputStream(new File("c:/myxml.xml")));

}

catch (JDOMException e)

{

e.printStackTrace();

}

catch (IOException e)

{

e.printStackTrace();

}

}

}