SAXReader

DOM4j读取XML文件（SAXReader)

一、

总结：

Document document=new SAXReader.reader(“xml文路径/文件名xxx.xml”);//得到Document对象

Element root = document.getRootElement()//获得根节点

Iterator iterator=root.elementIterator(); //从根节点遍历子节点

Iterator iterator=Element.elementIterator(); //再从子节点在遍历其子节点

对节点访问其属性用：Attribute leaderAttr =Element. attribute(“xxx”);

对节点访问其某个属性leaderAttr的名称：leaderAttr.getName()；
对节点访问其某个属性leaderAttr的值：leaderAttr.getValue()

对节点访问其名称：Element.getName();

对节点访问其文本：Element. getText();

简单代码为如下：

Document document=new SAXReader.reader(“xml文路径/文件名xxx.xml”);
Element root = document.getRootElement();

HashMap hm = new HashMap<String,String>();    
for ( Iterator iter = root.elementIterator(); iter.hasNext(); ) 
{   Element element = (Element) iter.next(); 
    Attribute ageAttr=element.attribute("age");
        String age = ageAttr.getValue();

。。。。。

for ( Iterator iterInner = element.elementIterator(); iterInner.hasNext(); ) {

Element elementInner = (Element) iterInner.next();

//遍历college节点开始

if(elementInner.getName().equals("college")){

/添加college的文本

hm.put(elementInner.getName()+ num, elementInner.getText());

//添加college的leader属性

Attribute leaderAttr=elementInner.attribute("leader");

。。。。。如果leaderAttr不是空字符或者其值不为null。。。。。

hm.put(elementInner.getName() + "-"+leaderAttr.getName()+ num,

leaderAttr.getValue());

}

else{ //遍历非college节点的其它节点

hm.put(elementInner.getName()+ num, elementInner.getText());

}

<?xml version="1.0" encoding="UTF-8"?>

<students>

<student age="25"><!--如果没有age属性，默认的为20-->

<name>崔卫兵</name>

<college>PC学院</college>

<telephone>62354666</telephone>

<notes>男,1982年生,硕士，现就读于北京邮电大学</notes>

</student>

<student>

<name>cwb</name>

<college leader="学院领导">PC学院</college><!--如果没有leader属性，默认的为leader-->

<telephone>62358888</telephone>

<notes>男,1987年生,硕士，现就读于中国农业大学</notes>

</student>

<student age="45">

<name>xxxxx</name>

<college leader="">xxx学院</college>

<telephone>66666666</telephone>

<notes>注视中，注释中</notes>

</student>

<student age="">

<name>lxx</name>

<college>yyyy学院</college>

<telephone>88888888</telephone>

<notes>注视中111，注释中222</notes>

</student>

</students>

Dom4jReadExmple.java

package test2;

import java.io.File;

import java.util.HashMap;

import java.util.Iterator;

import org.dom4j.Attribute;

import org.dom4j.Document;

import org.dom4j.DocumentException;

import org.dom4j.Element;

import org.dom4j.io.SAXReader;

public class Dom4jReadExmple {

public void iterateWholeXML(String filename,HashMap<String,String> hm){

SAXReader saxReader = new SAXReader();

try {

Document document = saxReader.read(new File(filename));

Element root = document.getRootElement();

//   用于记录学生编号的变量

int num=-1;

//遍历根结点（students）的所有孩子节点（肯定是student节点）

for ( Iterator iter = root.elementIterator(); iter.hasNext(); ) {

Element element = (Element) iter.next();

num++;

// 获取person节点的age属性的值

Attribute ageAttr=element.attribute("age");

if(ageAttr!=null){

String age = ageAttr.getValue();

if (age != null&&!age.equals("")) {

hm.put(element.getName() + "-"+ageAttr.getName()+ num, age);

} else {

hm.put(element.getName() + "-" +ageAttr.getName()+ num, "20");

}

}else{

hm.put(element.getName() + "-age"+ num, "20");

}

//遍历student结点的所有孩子节点（即name，college，telphone，notes），并进行处理

for ( Iterator iterInner = element.elementIterator(); iterInner.hasNext(); ) {

Element elementInner = (Element) iterInner.next();

if(elementInner.getName().equals("college")){

hm.put(elementInner.getName()+ num, elementInner.getText());

//获取college节点的leader属性的值

Attribute leaderAttr=elementInner.attribute("leader");

if(leaderAttr!=null){

String leader = leaderAttr.getValue();

if (leader != null&&!leader.equals("")) {

hm.put(elementInner.getName() + "-"+leaderAttr.getName()+ num, leader);

} else {

hm.put(elementInner.getName() + "-" +leaderAttr.getName()+ num, "leader");

}

}else {

hm.put(elementInner.getName() + "-leader"+ num, "leader");

}

}else{

hm.put(elementInner.getName()+ num, elementInner.getText());

}

}

}

} catch (DocumentException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}    
TestDom4jReadExmple.java

package dom4jExample.read;

import java.util.HashMap;

public class TestDom4jReadExmple {

public static void main(String[] args) {

try{

//获取解析完后的解析信息

HashMap<String,String> hashMap;

Dom4jReadExmple drb=new Dom4jReadExmple();

//遍历整个XML文件

hashMap = new HashMap<String,String>();

drb.iterateWholeXML("studentInfo.xml", hashMap);

System.out.println("姓名\t年龄\t学院\t学院领导\t电话\t\t备注");

for(int i=0;i<hashMap.size();i+=6){

int j=i/6;

System.out.print(hashMap.get("name"+j)+"\t");

System.out.print(hashMap.get("student-age"+j)+"\t");

System.out.print(hashMap.get("college"+j)+"\t");

System.out.print(hashMap.get("college-leader"+j)+"\t");

System.out.print(hashMap.get("telephone"+j)+"\t");

System.out.println(hashMap.get("notes"+j)+"\t");

}

}catch(Exception ex){

ex.printStackTrace();

}

}

}

二、

一个读写操作的例子：

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.InputStream;

import java.util.Iterator;

import org.dom4j.Document;

import org.dom4j.DocumentHelper;

import org.dom4j.Element;

import org.dom4j.io.SAXReader;

import org.dom4j.io.XMLWriter;

public class testXml {

public static void main(String[] args) {

try {

testXml test = new testXml();

test.testWrite();

test.testRead();

} catch (Exception e) {

e.printStackTrace();

}

}

public void testRead() throws Exception{

SAXReader reader = new SAXReader();

Document document = reader.read(new FileInputStream("src/output.xml"));

Element root = document.getRootElement();

for (Iterator iter = root.elementIterator(); iter.hasNext();) {

Element element = (Element) iter.next();

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

System.out.println(element.attributeValue("name"));

System.out.println(element.attributeValue("blog"));

}

}

public void testWrite() throws Exception{

Document document = DocumentHelper.createDocument();

Element root = document.addElement("root");

for(int i=0;i<10;i++){

Element element1 = root.addElement("user")

.addAttribute("name","Alex"+i)

.addAttribute("id", "id"+i)

.addText("我是信息");

}

XMLWriter writer = new XMLWriter(new FileOutputStream("src/output.xml"));

writer.write(document);

writer.close();

}

}

输出的效果：

<?xml version="1.0" encoding="UTF-8"?>

<root>

<user name="Alex0" id="id0">我是信息</user>

<user name="Alex1" id="id1">我是信息</user>

<user name="Alex2" id="id2">我是信息</user>

<user name="Alex3" id="id3">我是信息</user>

<user name="Alex4" id="id4">我是信息</user>

<user name="Alex5" id="id5">我是信息</user>

<user name="Alex6" id="id6">我是信息</user>

<user name="Alex7" id="id7">我是信息</user>

<user name="Alex8" id="id8">我是信息</user>

<user name="Alex9" id="id9">我是信息</user>

</root>