flex+java+blazeds 多通道好文

http://www.cnblogs.com/noam/archive/2010/08/05/1793504.html

blazeds, spring3整合实现RPC服务和消息服务

环境：

　　MyEclipse 7.5

　　Flash Builder 4 plugin for eclipse

　　Tomcat 6

　　BlazeDS 4.0.0

　　springframework 3.0.3

　　Spring-flex整合 org.springframework.flex-1.0.3.RELEASE.jar （适用于spring2.5.6+，blazeds3.2+）

步骤：

　　1. 创建带有Flex支持的Web工程，见通过J2EE Web工程添加Flex项目，进行BlazeDS开发。

　　2. 导入spring包和spring-flex集成包。

　　3. 配置web.xml，配置DispatcherServlet，使用spring进行管理，并将请求映射到MessageBroker。

　　4. 创建web-application-config.xml，配置flex服务，主要是在spring中配置MessageBroker。

　　5. 创建remoting-destination和 message-destination，修改channel属性。

　　6. 创建mxml文件，定义channelSet，注册remote-object和定义Productor, Consumer.

注意：

　　当不使用spring直接配置blazeDS实现RPC和消息服务时，仅需要在remoting-config.xml和messaging-config.xml中配置destination，只要在这些文件中配置了默认通道，mxml文件中不需要再定义channelSet即可执行。而使用spirng时，仅当将default-channels定义在services-config.xml的services标签中才有效，若在services-config.xml的services标签中加载其他配置文件，在这些文件中配置各自的default-channels，会报如下错误：[MessagingError message='×××'artgallerydataservice' either does not exist or the destination has no channels defined (and the application does not define any default channels.)']，原因是没有找到通道。如果仅将通道定义在<flex:message-destination>或<flex:remoting-destination>中，也会出现同样的情况。

　　对于以上的两个问题，我觉得几乎不可理解，解决方案是在mxml文件中定义channelSet以找到amf通道。

项目代码：

　　目录结构：

　　 

　　Web.xml:

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" 
    xmlns="http://java.sun.com/xml/ns/j2ee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee 
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
    
    <servlet>
      <servlet-name>Spring MVC Dispatcher Servlet</servlet-name>
      <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
      <init-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/web-application-config.xml</param-value>
      </init-param>
      <load-on-startup>1</load-on-startup>
    </servlet>
    
    <servlet-mapping>
      <servlet-name>Spring MVC Dispatcher Servlet</servlet-name>
      <url-pattern>/messagebroker/*</url-pattern>
    </servlet-mapping>
    
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

　　web-application-config.xml:

　　　　<flex:message-broker/>是非常重要的，它还有其它的几种表示方法，但以这种最为简单，它通过MessageBrokerHandlerAdapter和HandlerMapping将请求发送给spring管理的MessageBroker。

　　　　注意这里一定要导入spring-flex集成的schemaLocation，remoting-destination和 message-destination也在这里定义。

web-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/>

    <flex:message-destination id="msg_dest"/>
    <bean id="flex_test" class="test.Test">
        <flex:remoting-destination/>
    </bean>
</beans>

　　services-config.xml:

　　　　这里最重要的是channels的定义和配置。

services-config.xml

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

    <services>
      <default-channels>
        <channel ref="my-amf"/>
      </default-channels>
    </services>

    <security>
        <login-command class="flex.messaging.security.TomcatLoginCommand" server="Tomcat"/>
        <!-- Uncomment the correct app server
        <login-command class="flex.messaging.security.TomcatLoginCommand" server="JBoss">
        <login-command class="flex.messaging.security.JRunLoginCommand" server="JRun"/>        
        <login-command class="flex.messaging.security.WeblogicLoginCommand" server="Weblogic"/>
        <login-command class="flex.messaging.security.WebSphereLoginCommand" server="WebSphere"/>
        -->

        <!-- 
        <security-constraint id="basic-read-access">
            <auth-method>Basic</auth-method>
            <roles>
                <role>guests</role>
                <role>accountants</role>
                <role>employees</role>
                <role>managers</role>
            </roles>
        </security-constraint>
         -->
    </security>

    <channels>

        <channel-definition id="my-amf" class="mx.messaging.channels.AMFChannel">
            <endpoint url="http://{server.name}:{server.port}/{context.root}/messagebroker/amf" class="flex.messaging.endpoints.AMFEndpoint"/>
        </channel-definition>

        <channel-definition id="my-secure-amf" class="mx.messaging.channels.SecureAMFChannel">
            <endpoint url="https://{server.name}:{server.port}/{context.root}/messagebroker/amfsecure" class="flex.messaging.endpoints.SecureAMFEndpoint"/>
            <properties>
                <add-no-cache-headers>false</add-no-cache-headers>
            </properties>
        </channel-definition>

        <channel-definition id="my-polling-amf" class="mx.messaging.channels.AMFChannel">
            <endpoint url="http://{server.name}:{server.port}/{context.root}/messagebroker/amfpolling" class="flex.messaging.endpoints.AMFEndpoint"/>
            <properties>
                <polling-enabled>true</polling-enabled>
                <polling-interval-seconds>1</polling-interval-seconds>
            </properties>
        </channel-definition>

        <!--
        <channel-definition id="my-http" class="mx.messaging.channels.HTTPChannel">
            <endpoint url="http://{server.name}:{server.port}/{context.root}/messagebroker/http" class="flex.messaging.endpoints.HTTPEndpoint"/>
        </channel-definition>

        <channel-definition id="my-secure-http" class="mx.messaging.channels.SecureHTTPChannel">
            <endpoint url="https://{server.name}:{server.port}/{context.root}/messagebroker/httpsecure" class="flex.messaging.endpoints.SecureHTTPEndpoint"/>
            <properties>
                <add-no-cache-headers>false</add-no-cache-headers>
            </properties>
        </channel-definition>
        -->
    </channels>

    <logging>
        <target class="flex.messaging.log.ConsoleTarget" level="Error">
            <properties>
                <prefix>[BlazeDS] </prefix>
                <includeDate>false</includeDate>
                <includeTime>false</includeTime>
                <includeLevel>false</includeLevel>
                <includeCategory>false</includeCategory>
            </properties>
            <filters>
                <pattern>Endpoint.*</pattern>
                <pattern>Service.*</pattern>
                <pattern>Configuration</pattern>
            </filters>
        </target>
    </logging>

    <system>
        <redeploy>
            <enabled>false</enabled>
            <!-- 
            <watch-interval>20</watch-interval>
            <watch-file>{context.root}/WEB-INF/flex/services-config.xml</watch-file>
            <watch-file>{context.root}/WEB-INF/flex/proxy-config.xml</watch-file>
            <watch-file>{context.root}/WEB-INF/flex/remoting-config.xml</watch-file>
            <watch-file>{context.root}/WEB-INF/flex/messaging-config.xml</watch-file>
            <watch-file>{context.root}/WEB-INF/flex/data-management-config.xml</watch-file>
            <touch-file>{context.root}/WEB-INF/web.xml</touch-file>
             -->
        </redeploy>
    </system>

</services-config>

　　messaging-config.xml, proxy-config.xml, remoting-config.xml：

　　　　略。和blazeDS提供的几乎一样。

　　test.Test.java:

　　　　这里只定义了一个方法，用以测试远程方法调用。

package test;

public class Test {

    public void done(){
        System.out.println("OK.");
    }
}

　　flex_test.mxml:

　　　　这个不做过多解释。 这里定义了AMFChannel和ChannelSet，避免找不到通道的问题。Productor和Consumer是实现BlazeDS消息服务的两个组件，AsyncMessage是用来发送消息的。

flex_test.mxml

<?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"
               creationComplete="consumer.subscribe();">
    
    <fx:Script>
        <![CDATA[
            import mx.controls.Alert;
            import mx.messaging.messages.*;
            import mx.messaging.events.*;
            import mx.rpc.events.FaultEvent;
            import mx.rpc.events.ResultEvent;
            
            // Write received message to TextArea control.
            private function messageHandler(event: MessageEvent):void {
            ta.text += event.message.body + "\n";
            }
            
            // Compose the message as an instance of AsyncMessage, 
            // then use the Producer.send() method to send it.
            private function sendMessage():void {
                var message: AsyncMessage = new AsyncMessage();
                message.body = userName.text + ": " + msg.text;
                producer.send(message);
                msg.text = "";
            }
            
            protected function button_clickHandler(event:MouseEvent):void
            {
                // TODO Auto-generated method stub
                object.done();
            }
            
            protected function resulth(event:ResultEvent):void
            {
                label.text="succeed!";
            }
            
            protected function faulth(event:FaultEvent):void
            {
                label.text="failed!";
                Alert.show("远程对象调用失败:\n"+event.fault);
            }
            
        ]]>
    </fx:Script>
    
    <fx:Declarations>
        <!-- 将非可视元素（例如服务、值对象）放在此处 -->
        <mx:AMFChannel id="polling_amf" url="../messagebroker/amfpolling" />
        <mx:ChannelSet id="polling_channel" channels="{[polling_amf]}" />
        <mx:AMFChannel id="amf" url="../messagebroker/amf" />
        <mx:ChannelSet id="amf_channel" channels="{[amf]}" />
        
        <mx:Producer id="producer" destination="msg_dest" channelSet="{polling_channel}"/>
        <mx:Consumer id="consumer" destination="msg_dest" channelSet="{polling_channel}"
                     message="messageHandler(event)"/>
        
        <mx:RemoteObject id="object" destination="flex_test" 
                         channelSet="{amf_channel}" 
                         result="resulth(event);" fault="faulth(event);" />
        
    </fx:Declarations>
    <s:TextArea x="42" y="56" width="289" height="163" id="ta"/>
    <s:Label x="42" y="244" text="User Name"/>
    <s:Label x="43" y="272" text="Message"/>
    <s:TextInput x="120" y="237" width="128" id="userName"/>
    <s:TextInput x="120" y="267" id="msg"/>
    <s:Button x="261" y="237" label="Send" height="52" click="sendMessage();"/>
    <s:Label x="42" y="26" text="Message Content"/>
    <mx:VRule x="411" y="26" height="263"/>
    <s:Button x="468" y="54" label="RPC Service Test" width="148" height="39" id="button" click="button_clickHandler(event)"/>
    <s:Label y="140" text="Guess the Result!" verticalAlign="middle" textAlign="center" width="177" height="79" x="456" id="label"/>
</s:Application>

　　执行结果: