java send message to flex(BlazeDS)

最近公司想把flex与java后的通信成用BlazeDS，试了几天总算跑通了。
对BlazeDS不了解的可以先去这里了解下http://livedocs.adobe.com/blazeds/1/blazeds_devguide/

下面是步骤：
1.下载BlazeDS.war解压到%TOMCAT_HOME%/webapps目录下文件名为blazeds内包涵了WEB-INF和META－INF文件夹。
2.写一个flex的客户端 dsMessage.mxml

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical" 
	creationComplete="applicationInit()">
	<mx:Script>
		<![CDATA[
			import mx.messaging.ChannelSet;
			import mx.messaging.channels.AMFChannel;
			import mx.controls.Alert;
			import mx.messaging.events.MessageEvent;
			import mx.messaging.messages.AsyncMessage;
			import mx.messaging.events.MessageFaultEvent;
			import mx.messaging.events.MessageAckEvent;
			import mx.rpc.events.ResultEvent;
			import mx.rpc.events.FaultEvent;
			
			private function applicationInit():void{
				var url:String ="http://192.168.1.102/blazeds/"; //随便的以个blazeds应用 如果192.168.1.102改成 localhost后其它的电脑就访问不了。
//				var myStreamingAMF:StreamingAMFChannel = new StreamingAMFChannel(url+"my-streaming-amf", url+"messagebroker/streamingamf");
				var myPollingAMF:AMFChannel = new AMFChannel(url+"my-polling-amf", url+"messagebroker/amfpolling");
				myPollingAMF.pollingEnabled = true;//轮询
				myPollingAMF.pollingInterval = 1000;//隔多长时间询问一次 1miao
				var channelSet:ChannelSet = new ChannelSet();
//				channelSet.addChannel(myStreamingAMF);
				channelSet.addChannel(myPollingAMF);
							
				messageProducer.channelSet = channelSet;
				messageConsumer.channelSet = channelSet;
				
				messageConsumer.subscribe();				
			}
			
			private function addMessageToArea(message:String):void
			{
				chatMessagesArea.text = chatMessagesArea.text + "\n" + message;
			}
			
			private function handleResponse(event:MessageEvent):void
			{
				var message:String = null;
				message = event.message.headers["sender"] + ": " + event.message.body;
				addMessageToArea(message);	
			}
			private function sendMessage():void
			{
				var message:AsyncMessage = new AsyncMessage();
				message.headers = new Array();
				message.headers["sender"] = "sunny";
				message.body = chatMessageTxt.text;
				messageProducer.send(message);
				chatMessageTxt.text = "";
			}
			
			private function handleFaults(event:MessageFaultEvent):void
			{
				Alert.show(event.faultString);
			}
			
			private function handleAcknowledgements(event:MessageAckEvent):void
			{
				trace("done");
			}
			
		]]>
	</mx:Script>

	<mx:Producer id="messageProducer"
		destination="mychat"
		fault="handleFaults(event);"
		acknowledge="handleAcknowledgements(event)"
		/>
	<mx:Consumer id="messageConsumer"
		destination="mychat"		
		fault="handleFaults(event)"
		message="handleResponse(event)"
		/>
	<mx:VBox width="100%" height="100%">
		<mx:TextArea id="chatMessagesArea" editable="false"  width="100%" height="100%" 
			fontFamily="Georgia" fontSize="19" color="#2194AD"/>
		<mx:HBox width="100%" height="27">
			<mx:TextInput id="chatMessageTxt"  width="100%" height="100%" 
				fontFamily="Georgia" fontSize="15" enter="sendMessage()"/>
			<mx:Button id="chatMessageBtn" label="Send" width="64" 
				height="100%" click="sendMessage();"/>		
		</mx:HBox>						
	</mx:VBox>
	
</mx:Application>

3.写一个java类MessageSender

package com.kinorsoft;
import java.util.Date;

import flex.messaging.MessageBroker;
import flex.messaging.messages.AsyncMessage;

public class MessageSender {

	public void sendMessageToClients(String messageBody)
	{
		AsyncMessage msg = new AsyncMessage();

		msg.setClientId("Java-Based-Producer-For-Messaging");
		msg.setTimestamp(new Date().getTime());
		//you can create a unique id
		msg.setMessageId("Java-Based-Producer-For-Messaging-ID");
		//destination to which the message is to be sent
		msg.setDestination("mychat");		
		//set message body
		msg.setBody(messageBody != null?messageBody:"");
		//set message header
		msg.setHeader("sender", "From the server");

		//send message to destination
		MessageBroker.getMessageBroker(null).routeMessageToService(msg, null);			
	}

}

4.MessageSender.jsp调用上面的MessageSender.java

<%@page import="com.kinorsoft.MessageSender" %>
<%
	try
		{
	
		com.kinorsoft.MessageSender msg = new com.kinorsoft.MessageSender();
		msg.sendMessageToClients("This is from the jsp page");
		out.println("sent message");
		}
		catch(Exception e)
		{
	e.printStackTrace();
		}
%>

5.修改一下 WEB-INF/flex/messaging-config.xml
在<service>下加上
<destination id="mychat"></destination>

楼主还是长轮询，还是在隔一段时间，主动访问服务器，服务器压力很大啊，每一秒就要建立连接，请求好了，再关闭。不适合大量的用户使用。