xml..SAXBuilder

package com.tjsoft.demo;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.LinkedList;
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.XMLOutputter;

public class XmlTest {
 
 //查询所有的数据
 public static void list() throws JDOMException, IOException {
  SAXBuilder builder = new SAXBuilder();
  InputStream file = new FileInputStream("src/po.xml");
  //System.out.println(file.available());
  //获得文档对象
  Document document = builder.build(file);
  //获得根节点
  Element root = document.getRootElement();
  List list = root.getChildren();
  System.out.println("root : "+root);
  System.out.println(root.getName());
  Iterator it = list.iterator();
  //for(Element e:list) {
//  for(int i = 0; i < list.size(); i++){
  while(it.hasNext()){
   Element e = (Element) it.next();
   System.out.println("ID: "+e.getAttributeValue("id"));
   System.out.println(e.getChildText("username"));
   System.out.println(e.getChildText("password"));
   //System.out.println(list.iterator().getClass().toString());
   
  }
 }
 
 
 //添加数据
 public static void add() throws JDOMException, FileNotFoundException, IOException {
  SAXBuilder builder = new SAXBuilder();
  Document document = builder.build("src/po.xml");
  Element root = document.getRootElement();
  
  Element element = new Element("person");
  element.addAttribute("id","3");
  Element e1 = new Element("username");
  e1.setText("hello");
  Element e2 = new Element("password");
  e2.setText("world");
  
  element.addContent(e1);
  element.addContent(e2);
  root.addContent(element);
  document.setRootElement(root);
  
  XMLOutputter output = new XMLOutputter();
  output.output(document,new FileOutputStream("src/po.xml"));
  
  
 }
 //修改数据
 public static void edit(int id) throws JDOMException, FileNotFoundException, IOException {
  SAXBuilder builder = new SAXBuilder();
  Document document = builder.build("src/po.xml");
  Element root = document.getRootElement();
  

  List list = root.getChildren();
  Iterator it = list.iterator();  
  for(int i = 0; i < list.size(); i++) {
   Element e = (Element) it.next();
   System.out.println("=============="+e.getAttributeValue("id"));
   if(Integer.parseInt(e.getAttributeValue("id")) == id) {
    e.getChild("username").setText("wuchao");
    e.getChild("password").setText("jiayou");
    
   }
  }
  XMLOutputter output = new XMLOutputter();
  output.output(document,new FileOutputStream("src/po.xml"));
 }
 
 //删除
 public static void del(int id) throws JDOMException, FileNotFoundException, IOException {
  SAXBuilder builder = new SAXBuilder();
  Document document = builder.build("src/po.xml");
  Element root = document.getRootElement();
  
  List list = root.getChildren();
  Iterator it = list.iterator();
  
  for(int i = 0; i < list.size(); i++) {
   Element e = (Element) it.next();
   if(Integer.parseInt(e.getAttributeValue("id")) == id) {
    root.removeContent(e);
    break;
   }
  }
    //文件处理
    XMLOutputter out = new XMLOutputter();
    out.output(document, new FileOutputStream("src/po.xml"));
 }
 public static void main(String[] args) {
  
//   XmlTest.add();
//   XmlTest.edit(1);
   try {
    XmlTest.list();
   } catch (JDOMException e1) {
    // TODO 自动生成 catch 块
    e1.printStackTrace();
   } catch (IOException e1) {
    // TODO 自动生成 catch 块
    e1.printStackTrace();
   }
   try {
    try {
     XmlTest.del(1);
    } catch (FileNotFoundException e) {
     // TODO 自动生成 catch 块
     e.printStackTrace();
    } catch (IOException e) {
     // TODO 自动生成 catch 块
     e.printStackTrace();
    }
   } catch (JDOMException e) {
    // TODO 自动生成 catch 块
    e.printStackTrace();
   }
  
 }
}