关于Struts+Dwr 二级联动菜单的一个问题,请大家帮助

我写了一个XML
<?xml version="1.0" encoding="GBK"?>
<china>
<province name="直辖市">
<city>北京</city>
<city>上海</city>
<city>天津</city>
<city>重庆</city>
</province>
<province name="广东">
<city>广州</city>
<city>珠海</city>
<city>深圳</city>
<city>东莞</city>
</province>
<province name="广西">
<city>桂林</city>
<city>柳州</city>
<city>北海</city>
<city>南宁</city>
</province>
<province name="海南">
<city>海口</city>
<city>三亚</city>
</province>
<province name="湖北">
<city>武汉</city>
<city>鄂州</city>
<city>荆州</city>
<city>十堰</city>
</province>
<province name="湖南">
<city>长沙</city>
<city>岳阳</city>
<city>常德</city>
<city>张家界</city>
</province>
<province name="浙江">
<city>杭州</city>
<city>绍兴</city>
<city>宁波</city>
<city>台州</city>
</province>
<province name="辽宁">
<city>沈阳</city>
<city>大连</city>
<city>抚顺</city>
<city>铁岭</city>
</province>
</china>

然后写了一个Java类,用来读取省份和城市/
package com.selectdemo.struts.action;


import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.jdom.Document;
import org.jdom.Element;
import org.jdom.JDOMException;
import org.jdom.input.SAXBuilder;


public class ReadXml {
Element root = null;

public ReadXml() throws FileNotFoundException, JDOMException, IOException {
super();
SAXBuilder sb = new SAXBuilder();//解析器对象
Document doc = sb.build(new FileInputStream("src/com/selectdemo/struts/action/city.xml"));//绑定文件
root = doc.getRootElement();//获取根元素
}

public List getProvince(){//获取省份
ArrayList provinceList = new ArrayList();
List tempList = root.getChildren();//获取所有省份节点
for(int i=0; i<tempList.size();i++){
Element province=(Element)tempList.get(i);//子节点转型
provinceList.add(province.getAttributeValue("name"));//获取省份节点属性内容
}
return provinceList;
}

public List getCity(String province){
ArrayList cityList = new ArrayList();
List provincetemplist = root.getChildren();//省份集合
for(int i=0; i<provincetemplist.size();i++){
Element provinceElement = (Element)provincetemplist.get(i);
if((provinceElement.getAttributeValue("name")).equals(province)){//如果属性为传进来的名称
List cityTempList = provinceElement.getChildren();//获取子节点集合
for(int j=0; j<cityTempList.size(); j++){//循环
Element cityElement = (Element)cityTempList.get(j);//当前城市节点
cityList.add(cityElement.getTextTrim());//增加城市到集合
}
}
}
return cityList;
}

public static void main(String[] args) throws JDOMException, IOException{
//测试省份
ReadXml rx = new ReadXml();
List provincelist = rx.getProvince();
for(int i=0; i<provincelist.size(); i++){
System.out.println((String)provincelist.get(i));
}

//测试城市
List cityList = rx.getCity("直辖市");
for(int i=0; i<cityList.size(); i++){
System.out.println((String)cityList.get(i));
}
}
}

测试都已经成功,能分别返回省份和城市,经查询可以使用Dwr框架实现二级联动菜单,查了许多资料,但是基于Struts实现的却不多,实在无从下手,请大家给点解题思路或源码以供参考,谢谢大家,如有Struts的实例,如果方便的话,请发至邮箱:zhanghaidang@sina.com,急急