【推荐】Flex+Struts2+Spring整合开发实例

关于Flex的整合问题，做一个配置简介，另外对容易出错的地方跟大家说说 
如果有错误，感谢大家指正。 
(开始之前,我必须承认，题目是个噱头，只要有Spring这个超强粘合剂，多个框架可以很容易整合。) 
如果是熟悉Spring MVC则完全不需要使用Struts2，这里为了先前项目的表现层可以平滑过度到Flex，才沿用了Struts2 
另外，这里主要讲讲Flex怎么与Spring整合，至于Spring与其他框架整合，不在文章内 
1.假定你已经配置好web应用并且增加了BlazeDS和导入spring-flex包(使用到的包会在文章最后展示) 
配置web.xml 

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    id="WebApp_ID" version="2.5">

    <display-name>flexweb</display-name>
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>

    <!-- The filter for struts2 -->
    <filter>
        <filter-name>struts2</filter-name>
        <filter-class>
            org.apache.struts2.dispatcher.FilterDispatcher
        </filter-class>
    </filter>

    <listener>
        <listener-class>
            org.springframework.web.context.ContextLoaderListener
        </listener-class>
    </listener>
    <!-- Http Flex Session attribute and binding listener support -->
    <!--
        <listener>
        <listener-class>flex.messaging.HttpFlexSession</listener-class>
        </listener>
    -->

    <!-- MessageBroker Servlet 单独为Flex配置xml-->
    <servlet>
        <servlet-name>flex</servlet-name>
        <servlet-class>
            org.springframework.web.servlet.DispatcherServlet
        </servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>
                /WEB-INF/classes/flex-application-config.xml
            </param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <!-- The filter mapping for struts2 -->
    <filter-mapping>
        <filter-name>struts2</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--
    Map all /messagbroker requests to the DispatcherServlet for handling
    -->
    <servlet-mapping>
        <servlet-name>flex</servlet-name>
        <url-pattern>/messagebroker/*</url-pattern>
    </servlet-mapping>

    <welcome-file-list>
        <welcome-file>index.html</welcome-file>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
</web-app>

以上内容实质上是两个Web Framework,一个是Struts2(标记名为struts2)，一个是Spring MVC(标记名为flex) 
这里Spring MVC为flex的RemotingObject提供映射和Flex与Server通讯MessageBroker类 

配置flex-application-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:flex="http://www.springframework.org/schema/flex"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/flex
http://www.springframework.org/schema/flex/spring-flex-1.0.xsd">

    <flex:message-broker/>

大家注意到，标签引入http://www.springframework.org/schema/flex/spring-flex-1.0.xsd文件，便可以使用<flex:message-broker/> 标记了。 
但是这样写虽然简便，但在初学的时候，还是最好理解它的机制吧 
以上的内容可以改写成： 

（转载请注明出处：[url=http://www.live588.org]淘金盈[/url] [url=http://www.tswa.org]博彩通[/url]  [url=http://www.nsdm.org]澳门博彩[/url]  [url=http://www.lixx.org]博彩网[/url][url=http://www.uvip.org]e世博[/url][url=http://www.10086money.com]时尚资讯[/url][url=http://262002954-qq-com.iteye.com]flex[/url][url=http://flexflex.iteye.com]flex[/url]）

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:flex="http://www.springframework.org/schema/flex"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
<bean id="_messageBroker"
        class="org.springframework.flex.core.MessageBrokerFactoryBean">
        <property name="servicesConfigPath">
            <value>/WEB-INF/flex/services-config.xml</value>
        </property>
    </bean>
    <!-- Maps request paths at /* to the BlazeDS MessageBroker -->
    <bean
        class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
        <property name="mappings">
            <value>/*=_messageBroker</value>
        </property>
    </bean>

    <!-- Dispatches requests mapped to a MessageBroker -->
    <bean
        class="org.springframework.flex.servlet.MessageBrokerHandlerAdapter" />

大家注意： 
“http://www.springframework.org/schema/flex 
  http://www.springframework.org/schema/flex/spring-flex-1.0.xsd">内容被移除” 
完全是一个标准的Spring配置文件了。 
  这里把之前web.xml的/messagebroker/*映射完全对应到/*=_messageBroker，也就是 
org.springframework.flex.core.MessageBrokerFactoryBean类中，生成MessageBroker，而MessageBroker是Flex与Server通信的关键 
而MessageBrokerHandlerAdapter适配器会取得MessageBroker的实例，使用endpoint = broker.getEndpoint(endpointPath, contextPath);取得端点 
endpoint.service(request, response);发送 
如果你熟悉Spring MVC，请原谅我又唠叨一遍- -# 
现在通讯问题完毕，那么远程调用呢？ 
我们接着来： 
定义一个java类：

package example.fx;

public class DataBean {

    private String name = "";
    private String params = "";
    public String getName() {
        return this.getClass().getName()+ " : " +name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getParams() {
        return params;
    }
    public void setParams(String params) {
        this.params = params;
    }
}

在flex-application-config.xml中，增加： 
当然，你也可以写到Spring的其他配置文件中，例如本文中Spring管理Struts2的那个applicationContext.xml(参照web.xml)

<bean id="dataBean" class="example.fx.DataBean">
    <property name="params">
        <value>Hello Flex!!!</value>
    </property>
</bean>

这里只生成了一dataBean的实例，但是前段Flex如何访问呢？ 
在在flex-application-config.xml中继续增加

<flex:remoting-destination ref="dataBean" />

这里又是图开发速度，然而这部分可以有如下三种写法，分别是： 
a.

<bean id="dataBean" class="example.fx.DataBean">
           <property name="params">
               <value>Hello Flex!!!</value>
    </property>
    <flex:remoting-destination />
</bean>

b.

<flex:remoting-destination ref="dataBean"
        include-methods="read, update" exclude-methods="create, delete"
        channels="my-amf, my-secure-amf" />

c.

<bean id="product"
    class="org.springframework.flex.remoting.RemotingDestinationExporter">
    <property name="messageBroker" ref="_messageBroker" />
    <property name="service" ref="dataBean" />
    <property name="destinationId" value="dataBean" />
    <property name="includeMethods" value="read, update" />
    <property name="excludeMethods" value="create, delete" />
    <property name="channels" value="my-amf, my-secure-amf" />
</bean>

当然，dataBean中并没有read, update, create, delete方法,这里只是演示用. 
经过这么多繁琐的过程，终于Flex可以访问到Server的java类了。 
我们新建一个MXML Application文件

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
    <mx:Script>
        <![CDATA[
            import mx.rpc.events.FaultEvent;
            import mx.rpc.events.ResultEvent;
            private function onResultHandler(event:ResultEvent):void{
                Alert.show(String(event.result), String(example.data));
            }
            private function onFaultHandler(event:FaultEvent):void{
                Alert.show(String(event.fault), "Fault!");
            }
            private function btn_Click1EventHandler(event:MouseEvent):void{
                dbRemote.getName();
            }
            private function btn_Click1EventHandler(event:MouseEvent):void{
                dbRemote.getParams();
            }

        ]]>
    </mx:Script>
    <mx:RemoteObject id="dbRemote" destination="dataBean" endpoint="http://localhost:8080/flexweb/messagebroker/amf" result="onResultHandler(event)" fault="onFaultHandler(event)">
    </mx:RemoteObject>
    <mx:Button x="10" id="btn_Click1" label="RemoteClass->getName" click="btn_Click1EventHandler(event)"/>
    <mx:Button x="80" id="btn_Click2" label="RemoteClass->getParams" click="btn_Click2EventHandler(event)"/>
</mx:Application>

  服务器启动后，运行你的MXML Application,点击Flash上的两个按钮，看看结果吧 
如果你跟我一样懒 
那么配置一下Struts，在URL敲一下地址，不用每次都运行你的MXML文件，特别是为了安全起见，你把MXML文件编译到web/WEB-INF/下的时候 
以下是struts.xml

<!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
        "http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
    <package name="default" namespace="" extends="struts-default">
        <action name="*" class="com.opensymphony.xwork2.ActionSupport">
            <result name="success">/WEB-INF/page/flex/{1}.swf</result>
            </action>
    </package>
</struts>

有几点说明： 
1.flex的四个配置文件完全没有更改，并且使用默认channel. 
2.有文章说，在remoting-service配置远程访问 
比如：

<?xml version="1.0" encoding="UTF-8"?>
<service id="remoting-service"
    class="flex.messaging.services.RemotingService">

    <adapters>
        <adapter-definition id="java-object"
            class="flex.messaging.services.remoting.adapters.JavaAdapter"
            default="true" />
    </adapters>

    <default-channels>
        <channel ref="my-amf" />
    </default-channels>
        <!-- 远程调用 -->
    <destination id="dataBean">
        <properties>
            <source>example.fx.DataBean</source>
        </properties>
    </destination>
</service>

这种方式和在文章中的flex-application-config.xml配置的 
<flex:remoting-destination ref="dataBean" />  是一致的，也就是说，如果你在remoting-service配置了，就不需要在Spring配置文件中，反之亦然,如果你在remoting-service和flex-application-config.xml都配置了,web服务器启动的时候会抛异常,提示你bean id已经注册. 
3.有不少文章中，MXML中RomoteObject是这样配置的

<mx:AMFChannel id="myamf" uri="http://localhost:8080/flexweb/messagebroker/amf"/>
<mx:ChannelSet id="channelSet" channels="{[myamf]}"/>
<mx:RemoteObject id="dBean"
   destination="dataBean" channelSet="{channelSet}" result="onResultHandler(event)" fault="onFaultHandler(event)"/>

如果使用默认配置,即remoting-service.xml文件中会有一个默认channel配置，这样写是完全没有必要的，你只需要在

<mx:RemoteObject id="dbRemote" destination="dataBean" endpoint="http://localhost:8080/flexweb/messagebroker/amf"/>

 

定义一个server的端点 
上面的写法这相当于你另外写了一个AMFChannel，并且使用管道去接(ChannelSet里可以放很多channel) 

jar包： 
Spring 使用Spring 3.0.0.M2 
Struts 使用Struts 2.0.4 
Flex 使用默认BlazeDS包和org.springframework.flex-1.0.0.RC2.jar包 
稍后设置一下下载地址 
---------------------------------------------------------------- 
BlazeDS: 
http://opensource.adobe.com/wiki/display/blazeds/Release+Builds 
org.springframework.flex-1.0.0.RC2.jar: 

或http://dl.iteye.com/topics/download/6ba351cc-035b-39a4-b304-cca3e3bc6c50