xml文档的解析和生成（一）

xml文档主要有两种解析方式，DOM接口或SAX接口解析。

Dom解析示例：

1.建立DocumentBuilderFactory

2.建立DocumentBuilder

3.建立Document

4.建立NodeList

5.进行xml信息读取

xml文件放在D盘，为dom_demo_02.xml

<?xml version="1.0" encoding="GBK"?>
<addresslist>
<linkman>
<name> 张三 </name>
<email>[e-mail]</email>
</linkman>
<linkman>
<name> 李四 </name>
<email>[e-mail]</email>
</linkman>
</addresslist>

解析代码为：
import java.io.File;
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
* DOM解析xml文件
* @author win
*
*/
public class DomDemo01 {

/**
* @param args
*/
public static void main(String[] args) {
//1.建立DocumentBuilderFactory，用于取得DocumentBuilder
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

//2.通过DocumentBuilderFactory取得DocumentBuilder
DocumentBuilder builder = null;

try {
builder = factory.newDocumentBuilder();
} catch (ParserConfigurationException e) {
e.printStackTrace();
}

//3.定义Document接口对象，通过DocumentBuilder类进行DOM树的转换操作
Document doc = null;

try {
doc = builder.parse("D:"+File.separator+"dom_demo_02.xml");
} catch (SAXException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

//4.查找name节点
NodeList nl = doc.getElementsByTagName("linkman");

//输出NodeList中第一个子节点中的文本内容

for(int x=0;x<nl.getLength();x++){
Element e = (Element) nl.item(x);
System.out.println("姓名:"+e.getElementsByTagName("name").item(0).getFirstChild().getNodeValue());
System.out.println("姓名:"+e.getElementsByTagName("email").item(0).getFirstChild().getNodeValue());
}
//System.out.println("姓名:"+nl.item(0).getFirstChild().getNodeValue());
}

}

生成xml文件代码：

package com.hbut.xml;

import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;


/**
* 生成xml文件
* @author win
*
*/
public class DomDemo03 {

public static void main(String[] args) {

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = null;
try {
builder =factory.newDocumentBuilder();
} catch (ParserConfigurationException e) {
e.printStackTrace();
}

Document doc = null;
doc = builder.newDocument();

//建立各个节点
Element addresslist = doc.createElement("addresslist");
Element linkname = doc.createElement("linkname");
Element name = doc.createElement("name");
Element email = doc.createElement("email");
//设置各个操作节点,为节点添加文本
name.appendChild(doc.createTextNode("李兴华"));
email.appendChild(doc.createTextNode("[e-mail]"));
//设置节点关系
linkname.appendChild(name);
linkname.appendChild(email);
addresslist.appendChild(linkname);
doc.appendChild(addresslist);
//输出文档到文件中
TransformerFactory tf = TransformerFactory.newInstance();
Transformer t = null;

try {
t = tf.newTransformer();
} catch (TransformerConfigurationException e) {
e.printStackTrace();
}

t.setOutputProperty(OutputKeys.ENCODING, "GBK");
DOMSource source = new DOMSource(doc);
StreamResult result = new StreamResult(new File("D:"+File.separator+"output.xml"));

try {
t.transform(source, result);
} catch (TransformerException e) {
e.printStackTrace();
}
}

}