Flex与java交互方法之HttpService

地球已经调至震动状态使用flex中的httpservice方法与java进行交互：

一、写服务器:

    1.在myeclipse中建立web项目

    2.写一个用来打印xml的servlet

    3.当使用httpservice与java进行交互的时候不用改写remoting-config.xml文件

    4.web.xml文件中配置servlet的访问地址(一般不用配置，当一个servlet建好之后myeclipse就会自动配置好web.xml文 件，不用去改动，但是需要注意的是，当你在导入blazeds开发文件的时候他会改动web.xml文件，这时候你一定要将web.xml文件改过来，要 不然flex在访问服务器的时候则反问不到你的servlet)。

    5.当你的服务器端的servlet写好之后再去建立flex 项目，并且根据你之前建好的servlet项目在flex项目的属性项中配置flex服务器的访问地址。

    6.写flex的mxml文件。

二、一个简单案例：

   1.servlet源代码

  package com.wle.flex.HttpService.java文件源代码

 

   package com.wle.flex;

  import java.io.IOException;

  import java.io.Writer;

  import javax.servlet.ServletException;

  import javax.servlet.http.HttpServlet;

  import javax.servlet.http.HttpServletRequest;

  import javax.servlet.http.HttpServletResponse;

  public class HttpService01 extends HttpServlet {

 

    public void doGet(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {

        response.setContentType("text/xml;charset=utf-8");

        Writer out = response.getWriter();

        out.write("<?xml version='1.0' encoding='utf-8'?>");

        out.write("<item>");

        out.write("<student name='林冲' age='23' class='水泊梁山一班'/>");

        out.write("<student name='李逵' age='24' class='水泊梁山二班'/>");

        out.write("<student name='扈三娘' age='23' class='水泊梁山一班'/>");

        out.write("<student name='时迁' age='24' class='水泊梁山二班'/>");

        out.write("<student name='武松' age='23' class='水泊梁山一班'/>");

        out.write("<student name='燕青' age='24' class='水泊梁山二班'/>");

        out.write("</item>");

    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {

        this.doGet(request, response);

    }

  }

 

 2.servlet对应的web.xml文件

  <?xml version="1.0" encoding="UTF-8"?>

  <web-app version="3.0"

     xmlns="http://java.sun.com/xml/ns/javaee"

     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee

     http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
     <display-name></display-name>

   <servlet>

     <description>This is the description of my J2EE component</description>

     <display-name>This is the display name of my J2EE component</display-name>

     <servlet-name>HttpService01</servlet-name>

     <servlet-class>com.wle.flex.HttpService01</servlet-class>

   </servlet>

   <servlet-mapping>

     <servlet-name>HttpService01</servlet-name>

     <url-pattern>/wl/HttpService01</url-pattern>

   </servlet-mapping>   

 

  </web-app>

  3.在webroot目录下导入blazeds文件

    

  4.发布servlet项目

     比如讲servlet项目发布到D:\Tomcat 6.0\webapps\flex_service_HttpService这个文件下

    

  5.建立flex项目

    建好flex项目之后，在项目上右键单击选择属性，在属性中的flex服务器选项中设置flex服务器的地址

    配置信息如下:

     文件根目录:D:\Tomcat 6.0\webapps\flex_service_HttpService

     根URL(U)：http://localhost:8089/flex_service_HttpService

     上下文根目录:/flex_service_HttpService

   6.配置好flex项目的服务器之后就开始写flex源文件，如下：

   <?xml version="1.0" encoding="utf-8"?>

   <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"

                layout="vertical"

                fontSize="12" viewSourceURL="srcview/index.html" xmlns:s="library://ns.adobe.com/flex/spark">

   

    <!--<mx:Style source="DGtoExcel.css"/>-->

   

   

    <mx:Script>

        <![CDATA[

            import mx.collections.ArrayCollection;

            import mx.controls.Alert;

            import mx.events.FlexEvent;

            import mx.events.ItemClickEvent;

            import mx.rpc.events.FaultEvent;

           

           

           

            [Bindable]

            private var myAC:ArrayCollection;

           

            private function faultHandler(event:FaultEvent):void

            {

                Alert.show(event.fault.faultString, event.fault.message);

            }

           

            // Function to filter out all items with gender

            private function maleFilterFunc(item:Object):Boolean {

                return item.gender == 1;

            }

           

            // Function to apply the filter function the ICollectionView.

            private function filterMale():void {

                myAC.filterFunction = maleFilterFunc;

                //Refresh the collection view to apply the filter.

                myAC.refresh();

            }

           

            // Function to filter out all items with gender

            private function femaleFilterFunc(item:Object):Boolean {

                return item.gender == 0;

            }

           

            // Function to apply the filter function the ICollectionView.

            private function filterFemale():void {

                myAC.filterFunction = femaleFilterFunc;

                //Refresh the collection view to apply the filter.

                myAC.refresh();

            }

           

            // Function to Reset the view to its original state.

            private function resetAC():void {

                myAC.filterFunction = null;

                //Refresh the collection view.

                myAC.refresh();

            }

           

           

            // Event handler function to display the selected button

            private function filterHandler(event:ItemClickEvent):void {

                switch(event.currentTarget.selectedValue){

                    case 1:

                        filterMale();

                        break;

                    case 0:

                        filterFemale();

                        break;

                    case 2:

                        resetAC();

                        break;

                    default:

                        break;   

                }

               

            }           

           

            protected function bt1_clickHandler():void

            {

                myService.send();

            }

           

        ]]>

    </mx:Script>

    <mx:HTTPService id="myService"

                    showBusyCursor="true"

                    url="http://localhost:8089/flex_service_HttpService/wl/HttpService01"

                    result="myAC = event.result.item.student"

                    fault="faultHandler(event)"

                    contentType="application/xml"

                    />

    <mx:HBox>

        <mx:RadioButtonGroup id="gendertype" itemClick="filterHandler(event);"/>

        <mx:RadioButton groupName="gendertype" id="rbMale" value="1" label="男" />

        <mx:RadioButton groupName="gendertype" id="rbFemale" value="0" label="女" />

        <mx:RadioButton groupName="gendertype" id="rbAll" value="2" label="所有" />

    </mx:HBox>

    <mx:DataGrid id="myDG" width="100%" rowCount="20"

                 dataProvider="{myAC}" >

        <mx:columns>       

            <mx:DataGridColumn headerText="姓名" dataField="name"/>           

            <mx:DataGridColumn headerText="年龄" dataField="age" />

            <mx:DataGridColumn headerText="班级" dataField="class"/>

        </mx:columns>

    </mx:DataGrid>   

    <mx:HBox>

        <s:Button id="bt1" label="提交" click="bt1_clickHandler()"/>

    </mx:HBox>

   </mx:Application>

   这样就实现了flex到javaee 的交互工作