flex中httpservice与java后台交互的两种传值方式

环境：myeclipse8.5+flex4+blazeds
            描述：flex4中httpservice与服务器端交互的值传递问题
            方式一：通过<s:request/>标签进行交互，在该标签内部以要传递的参数名作为该标签内的子标签，值作为内容进行传递，服务端接受数据采用request.getParmeter("参数名")获取数据.
            示例代码：
            flex中的代码：

<!--定义HttpService发送请求-->
        <s:HTTPService id="service" 
                       url="http://localhost:8080/testhttpservice/testHttpServiceServlet" 
                       useProxy="false" 
                       fault="service_faultHandler(event)" 
                       result="service_resultHandler(event)">
            <!--第一种传值方式-->
            
            <s:request >
                <!--参数名称作标签,中间填充参数值-->
                <username>{txtusername.text}</username>
                <password>{txtpassword.text}</password>
            </s:request>
            
        </s:HTTPService>

        后台接受参数的代码：

        //获取flex传递的参数 username password
        String username=request.getParameter("username");
        //get方式处理乱码
        //username=new String(username.getBytes("ISO-8859-1"),"utf-8");
        String password=request.getParameter("password");
        //password=new String(password.getBytes("ISO-8859-1"),"utf-8");

        方式二：第二种传值方式通过send()方法传值send方法中传递参数 ，服务端接受数据采用request.getParmeter("参数名")获取数据.
        示例代码：

                //第二种传值方式 通过send()方法传值 send方法中传递参数 
                //定义一object对象
                var val:Object=new Object();
                //分别将文本框username，password的值传递到后台
                //object对象.参数名=值   传值操作
                val.username=txtusername.text;
                val.password=txtpassword.text;
                service.send(val);

        贴出完整的代码：
        服务器端:

package com.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * 功能描述:flex httpservice与java交互参数传递探讨<br>
 * @author sxyx2008<br>
 * @date 2010-07-19
 *
 */
@SuppressWarnings("serial")
public class TestHttpServiceServlet extends HttpServlet {
    
    @Override
    protected void service(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //处理post方式乱码
        request.setCharacterEncoding("utf-8");
        //设置浏览器输出字符编码
        response.setCharacterEncoding("utf-8");
        PrintWriter writer=response.getWriter();
        //获取flex传递的参数 username password
        String username=request.getParameter("username");
        //get方式处理乱码
        
        //username=new String(username.getBytes("ISO-8859-1"),"utf-8");
        String password=request.getParameter("password");
        //password=new String(password.getBytes("ISO-8859-1"),"utf-8");
        
        //构建一个list存放一些数据用来模拟用户是否存在这一功能
        List<String> list=new ArrayList<String>();
        list.add("张三");
        list.add("李四");
        list.add("王五");
        list.add("曹操");
        list.add("孙权");
        list.add("刘备");
        //检验用户
        if(list.contains(username)){
            writer.print("存在:"+username+"客户端传递的密码是:"+password);
        }else{
            writer.print("找不到:"+username+"客户端传递的密码是:"+password);
        }
        
    }
}

        flex代码：

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
               xmlns:s="library://ns.adobe.com/flex/spark" 
               xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
    <fx:Script>
        <![CDATA[
            import mx.controls.Alert;
            import mx.rpc.events.FaultEvent;
            import mx.rpc.events.ResultEvent;

            //调用失败
            protected function service_faultHandler(event:FaultEvent):void
            {
                Alert.show("失败了:"+event.message,"提示");
            }

            //调用成功
            protected function service_resultHandler(event:ResultEvent):void
            {
                Alert.show("成功了:"+event.result as String,"提示");
            }
    
            //调用
            protected function button1_clickHandler(event:MouseEvent):void
            {
                //第一种传值方式                
                //service.send();
                
                //第二种传值方式 通过send()方法传值 send方法中传递参数 
                //定义一object对象
                var val:Object=new Object();
                //分别将文本框username，password的值传递到后台
                //object对象.参数名=值   传值操作
                val.username=txtusername.text;
                val.password=txtpassword.text;
                service.send(val);
            }

        ]]>
    </fx:Script>
    <fx:Declarations>
        <!-- 将非可视元素（例如服务、值对象）放在此处 -->
        <!--定义HttpService发送请求-->
        <s:HTTPService id="service" 
                       url="http://localhost:8080/testhttpservice/testHttpServiceServlet" 
                       useProxy="false" 
                       fault="service_faultHandler(event)" 
                       result="service_resultHandler(event)">
            <!--第一种传值方式-->
            
            <s:request >
                <!--参数名称作标签,中间填充参数值-->
                <username>{txtusername.text}</username>
                <password>{txtpassword.text}</password>
            </s:request>
            
        </s:HTTPService>
        
        
    </fx:Declarations>
    <s:TextInput x="332" y="196" id="txtusername"/>
    <s:TextInput x="332" y="256" id="txtpassword" displayAsPassword="true"/>
    <s:Button x="357" y="311" label="发送" click="button1_clickHandler(event)"/>
    <s:Label x="290" y="206" text="用户名:"/>
    <s:Label x="297" y="266" text="密码:"/>
</s:Application>