借助XStream，对象，xml和字符串之间互相转化

package com.joe.test.xstream;

import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;

import com.joe.test.json.User;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.xml.DomDriver;

/**
 * @author joe
 */
public class XstreamTest {
    public static void main(String[] args) {
        User user1 = new User();
        user1.setUsername("username1");
        user1.setPassword("password1");
        User user2 = new User();
        user2.setUsername("username2");
        user2.setPassword("password2");
        Map<String,User> userMap = new HashMap<String,User>();
        userMap.put(user1.getUsername(), user1);
        userMap.put(user2.getUsername(), user2);
        XStream xStream = new XStream(new DomDriver());
        String xml = xStream.toXML(userMap);
        
        
        
        Map<String,User> uMap = (Map<String,User>) xStream.fromXML(xml);
        for(Entry<String,User> entry:uMap.entrySet()){
            User u = entry.getValue();
            System.out.println("key="+entry.getKey()+",username="+u.getUsername()+",password="+u.getPassword());
        }
    }
}