java解析xml简单事例

DOM,SAX,JDOM,DOM4J

创建一个简单的XML文档

<?xml version="1.0" encoding="gbk"?>

<users xmlns="http://www.softteem.com/xml">

   <user id="1">

      <name>Element</name>

      <pass>123</pass>

   </user>

   <user id="2">

       <name>jack</name>

       <pass>456</pass>

   </user>

   <!-- .............. -->

</users>

DOM解析myusers.xml的简单例子及DOM生成newusers.xml的简单例子

import java.io.File;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.transform.Transformer;

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;

import org.w3c.dom.NodeList;



public class TestDOM {

    public static void main(String[] args) {

       try {

           // 获得一个新的DocumentBuilderFactory实例

           DocumentBuilderFactory factory = DocumentBuilderFactory

                  .newInstance();

           // 使用DocumentBuilderFactory构建DocumentBulider

           DocumentBuilder builder = factory.newDocumentBuilder();

           // 使用DocumentBuilder的parse()方法解析文件

           Document doc = builder.parse(new File(

                  "src/com/java/xml/myusers.xml"));

           // 将已解析的文档存储在Document对象中

           NodeList nodeList = doc.getElementsByTagName("user");

           // 使用getElementByTagName()方法获得元素

           for (int i = 0; i < nodeList.getLength(); i++) {

              Element user = (Element) nodeList.item(i);

              System.out.println("id:" + user.getAttribute("id"));

              String name = user.getElementsByTagName("name").item(0)

                     .getFirstChild().getNodeValue();

              System.out.println("name:" + name);

              String pass = user.getElementsByTagName("pass").item(0)

                     .getFirstChild().getNodeValue();

              System.out.println("pass:" + pass);

              newXML();

           }

       } catch (Exception e) {

           e.printStackTrace();

       }

    }



    public static void newXML() {

       Element users, user, name, pass;

       try {

           DocumentBuilderFactory factory = DocumentBuilderFactory

                  .newInstance();

           DocumentBuilder bulider = factory.newDocumentBuilder();

           Document doc = bulider.newDocument();

           if (doc != null) {

              users = doc.createElement("users");

              user = doc.createElement("user");

              user.setAttribute("id", "01");

              name = doc.createElement("name");

              name.appendChild(doc.createTextNode("rose"));

              pass = doc.createElement("pass");

              pass.appendChild(doc.createTextNode("123"));

              user.appendChild(name);

              user.appendChild(pass);

              users.appendChild(user);

              doc.appendChild(users);

              TransformerFactory tf = TransformerFactory.newInstance();

              Transformer former = tf.newTransformer();

              DOMSource source = new DOMSource(doc);

              StreamResult result = new StreamResult(new File(

                     "src/com/java/xml/newusers.xml"));

              former.transform(source, result);

           }

       } catch (Exception e) {

           e.printStackTrace();

       }

    }

}

SAX解析myusers.xml的简单例子

import java.io.File;

import java.util.Stack;

import javax.xml.parsers.SAXParser;

import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;

import org.xml.sax.SAXException;

import org.xml.sax.helpers.DefaultHandler;



public class TestSAX extends DefaultHandler {

    private Stack stack = new Stack();



    public static void main(String[] args) {

       try {

           // 创建SAXParserFactory实例

           SAXParserFactory factory = SAXParserFactory.newInstance();

           // 创建SAXParser实例

           SAXParser parser = factory.newSAXParser();

           // 使用parse()方法解析XML文档

           parser.parse(new File("src/com/java/xml/myusers.xml"),

                  new TestSAX());

       } catch (Exception e) {

           e.printStackTrace();

       }

    }



    @Override

    public void characters(char[] ch, int start, int length)

           throws SAXException {

       String value = new String(ch, start, length);

       String name = (String) stack.peek();

       if (name.equals("name")) {

           System.out.println("name:" + value);

       } else if (name.equals("pass")) {

           System.out.println("pass:" + value);

       }

    }



    @Override

    public void endDocument() throws SAXException {

       System.out.println("... end document!");

    }



    @Override

    public void endElement(String uri, String localName, String name)

           throws SAXException {

       stack.pop();

    }



    @Override

    public void startDocument() throws SAXException {

       System.out.println("start document ....");

    }



    @Override

    public void startElement(String uri, String localName, String name,

           Attributes attributes) throws SAXException {

       stack.push(name);

       String id = attributes.getValue("id");

       if (id != null) {

           System.out.println("id" + id);

       }

    }

}

JDOM解析myusers.xml的简单例子

import java.io.File;

import java.util.List;

import org.jdom.Document;

import org.jdom.Element;

import org.jdom.Namespace;

import org.jdom.input.SAXBuilder;



public class TestJDOM {

    public static void main(String[] args) {

       try {

           SAXBuilder builder = new SAXBuilder();

           Document doc = builder.build(new File(

                  "src/com/java/xml/myusers.xml"));

           Element root = doc.getRootElement();

           Namespace ns = root.getNamespace();

           List users = root.getChildren();

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

              Element user = (Element) users.get(i);

              String id = user.getAttributeValue("id");

              System.out.println("id:" + id);

              String name = user.getChild("name", ns).getValue();

              System.out.println("name:" + name);

              String pass = user.getChild("pass", ns).getValue();

              System.out.println("pass:" + pass);

           }

       } catch (Exception e) {

           e.printStackTrace();

       }

    }

}

DOM4J解析myusers.xml的简单例子

import java.io.File;

import java.util.Iterator;

import org.dom4j.Document;

import org.dom4j.Element;

import org.dom4j.io.SAXReader;



public class TestDOM4J {

    public static void main(String[] args) {

       try {

           SAXReader reader = new SAXReader();

           Document doc = reader

                  .read(new File("src/com/java/xml/myusers.xml"));

           Element root = doc.getRootElement();

           Iterator iterator = root.elementIterator("user");

           while (iterator.hasNext()) {

              Element user = (Element) iterator.next();

              String id = user.attributeValue("id");

              System.out.println("id:" + id);

              String name = user.elementText("name");

              System.out.println("name:" + name);

              String pass = user.elementText("pass");

              System.out.println("pass:" + pass);

           }

       } catch (Exception e) {

           e.printStackTrace();

       }

    }

}