Java与Flex学习笔记(5)----Flex与Java通信之HttpService方式
Flex用RemoteObject方式与Java通信是最常用的方式,这是一种最直观的方式。当然Flex也可以用HttpService与服务器类如servlet通信,这也是本次学习的重点。
这次学习是在上节的基础上进行的。本节学习用到的LoginEvent.as,LoginModule.mxml文件代码如上节所示。
好了,新建一个servlet类LoginServlet.java,代码如下所示:
- package com.yqsn.servlet;
- import java.io.IOException;
- import java.io.PrintWriter;
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
- public class LoginServlet extends HttpServlet {
- @Override
- protected void service(HttpServletRequest req, HttpServletResponse resp)
- throws ServletException, IOException {
- // TODO Auto-generatedmethod stub
- req.setCharacterEncoding("utf-8");
- resp.setCharacterEncoding("utf-8");
- PrintWriter out=resp.getWriter();
- String username=req.getParameter("username");
- String passworld=req.getParameter("passworld");
- //System.out.println(username+":"+passworld);
- if(username.equals("admin")&& passworld.equals("123")){
- out.print(true);
- }else{
- out.print(false);
- }
- }
- }
这个servlet在web.xml中的配置如下所示:
- <servlet>
- <servlet-name>LoginServlet</servlet-name>
- <servlet-class>com.yqsn.servlet.LoginServlet</servlet-class>
- </servlet>
- <servlet-mapping>
- <servlet-name>LoginServlet</servlet-name>
- <url-pattern>/LoginServlet</url-pattern>
- </servlet-mapping>
将MyEclipse切换到flash视图,新建一个application文件HttpServiceDemo.mxml,代码如下所示:
- <?xmlversionxmlversion="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 com.flex.ases.LoginEvent;
- import com.flex.ases.LoginMess;
- import com.flex.module.LoginModule;
- import mx.controls.Alert;
- import mx.managers.PopUpManager;
- import mx.rpc.events.FaultEvent;
- import mx.rpc.events.ResultEvent;
- private var loginModule:LoginModule=new LoginModule();
- [Bindable]
- private var username:String;
- [Bindable]
- private varpassworld:String;
- protected function login_clickHandler(event:MouseEvent):void
- {
- // TODOAuto-generated method stub
- PopUpManager.addPopUp(loginModule,this,true);
- PopUpManager.centerPopUp(this.loginModule);
- loginModule.addEventListener(LoginEvent.LOGIN_EVENT,loginHander);
- }
- public function loginHander(event:LoginEvent):void{
- //varobj:Object=event.loginMess as Object;
- username=event.loginMess['username'];
- passworld=event.loginMess['passworld'];
- httpServiceSend.send();
- }
- protected function httpServiceSend_faultHandler(event:FaultEvent):void
- {
- // TODOAuto-generated method stub
- Alert.show(event.fault.message as String,"提示");
- }
- protected function httpServiceSend_resultHandler(event:ResultEvent):void
- {
- // TODOAuto-generated method stub
- var result:Boolean=event.result as Boolean;
- if(result==true){
- Alert.show(username+",欢迎您回来!","提示");
- aaa.text=username+",欢迎您回来!";
- login.label="";
- bbb.text="";
- }else{
- Alert.show("对不起,用户名或密码不存在!","提示");
- }
- //Alert.show("成功了!");
- }
- ]]>
- </fx:Script>
- <fx:Declarations>
- <!-- Place non-visualelements (e.g., services, value objects) here -->
- <s:HTTPService id="httpServiceSend" url="http://localhost:8000/JavaAndFlexDemo/LoginServlet" useProxy="false"fault="httpServiceSend_faultHandler(event)"result="httpServiceSend_resultHandler(event)" >
- <s:request >
- <username>{username}</username>
- <passworld>{passworld}</passworld>
- </s:request>
- </s:HTTPService>
- </fx:Declarations>
- <s:Label x="200" y="150" width="182" height="27" fontSize="18" id="aaa" text="您还没有登陆,现在就" verticalAlign="middle"/>
- <mx:LinkButton x="393" y="150" width="57" height="27" label="登陆" id="login" fontSize="18"click="login_clickHandler(event)"/>
- <s:Label x="459" y="150" width="37" height="27" id="bbb" fontSize="18" text="吧!" verticalAlign="middle"/>
- </s:Application>
从代码中我们可以看出,我们先定义一个HttpServlet发送请求httpServiceSend,然后通过下面这种方式存值:
- <s:request >
- <username>{username}</username>
- <passworld>{passworld}</passworld>
- </s:request>
这种方式很简单,我们在后台通过request. getParameter(“参数名”)取值就可以了,当然我们也可以在loginHander(event:LoginEvent)函数中通过下面方式存值并发送请求:
- public functionloginHander(event:LoginEvent):void{
- //varobj:Object=event.loginMess as Object;
- username=event.loginMess['username'];
- passworld=event.loginMess['passworld'];
- var obj:Object=new Object;
- obj.username=username;
- obj.passworld=passworld;
- httpServiceSend.send(obj);
- }
运行结果是一样的,你可以试试。
好了,程序算是完成了,现在开始验收结果。
打开服务器并部署项目,运行felx页面RemoteObjectDemo.mxml,如下所示:
当我们点击“登陆”按钮后,弹出module页面,如下所示:
当我们输入的用户名和密码都正确时则提示你登陆正确:
输入错误则提示你输入不正确:
可以看出,我们输入的用户名与密码已经用httpservice方式发送到后台并且成功接受了并将结果返回给前台了。
好了,就学习这么多,下节将学习WebService方式。
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