Flex采用blazeds实现服务器向（特定标识的）客户端推数据(基于consumer模式)

前言：
有很多类似股票、外汇、期货等实时行情这种应用，客户端需要显示行情牌价等信息。
目前的作法是：客户端定时向服务器请求，无论数据是否有更新，都把数据发到客户端。
我们这里讲的一种技术不同以上这个做法，我们是采用服务器向客户端推的这种方式，该方式的好处不言自明。blazeds中有一个名为：StreamingAMFChannel　的通道，我们就是采用它来实现向客户端推这个功能。
Tick.java :

package test;

import java.math.BigDecimal;
import java.util.Date;

public class Tick {
    private BigDecimal askPrice;

    private BigDecimal bidPrice;

    private BigDecimal midPrice;

    private Date tickTime;

    private String seqno;

    public String getSeqno() {
        return seqno;
    }

    public void setSeqno(String seqno) {
        this.seqno = seqno;
    }

    public BigDecimal getAskPrice() {
        return askPrice;
    }

    public void setAskPrice(BigDecimal askPrice) {
        this.askPrice = askPrice;
    }

    public BigDecimal getBidPrice() {
        return bidPrice;
    }

    public void setBidPrice(BigDecimal bidPrice) {
        this.bidPrice = bidPrice;
    }

    public BigDecimal getMidPrice() {
        return midPrice;
    }

    public void setMidPrice(BigDecimal midPrice) {
        this.midPrice = midPrice;
    }

    public Date getTickTime() {
        return tickTime;
    }

    public void setTickTime(Date tickTime) {
        this.tickTime = tickTime;
    }

}

FeedThread .java :

public static class FeedThread extends Thread {
  private String uid;
  
        public void setUid(String uid) {
   this.uid = uid;
  }

  public FeedThread(String uid){
         this.uid = uid;
        }
        public boolean running = true;

        public void run() {
            MessageBroker msgBroker = MessageBroker.getMessageBroker(null);
            String clientID = UUIDUtils.createUUID();
            int i = 0;
            while (running) {
                Tick tick = new Tick();
                tick.setAskPrice(new BigDecimal("100"));
                tick.setBidPrice(new BigDecimal("100"));
                tick.setMidPrice(new BigDecimal("100"));
                tick.setTickTime(new Date());

                tick.setSeqno(String.valueOf(i));
                System.out.println(i+"--"+uid);
               
                AsyncMessage msg = new AsyncMessage();
                msg.setDestination("tick-data-feed");
                msg.setHeader("DSSubtopic", "tick"+uid);
                msg.setClientId(clientID);
                msg.setMessageId(UUIDUtils.createUUID());
                msg.setTimestamp(System.currentTimeMillis());
                
                msg.setBody(tick);
                
                msgBroker.routeMessageToService(msg, null);
               
                i++;
                try {
                    Thread.sleep(20);
                } catch (InterruptedException e) {
                }

            }
        }
    }

UserService.java :

package sws.service;

import module.User;

public interface UserService {
  public void Test(String uid);
  public void stop(String uid);
}

UserServiceImpl.java :

package sws.service;

import java.util.HashMap;
import java.util.Map;

import module.User;

import org.springframework.beans.factory.annotation.Autowired;

import sws.dao.UserDao;
import test.TickServlet.FeedThread;

public class UserServiceImpl implements UserService {
 private static Map<String,Thread> map = new HashMap<String,Thread>();

 public void Test(String uid) {
   Boolean b = map.containsKey(uid);
   if(!b){
   FeedThread thread = new FeedThread(uid);
   thread.start();
   map.put(uid, thread);
   }
 }

 public void stop(String uid) {
  FeedThread thread = (FeedThread)map.get(uid);
  thread.running = false;
 }

}

下一步加入flex配置文件。
flex的配置文件默认有四个，文件目录在WebContent\WEB-INF\flex目录下。
messaging-config.xml
proxy-config.xml
remoting-config.xml
services-config.xml
其实，这中间用的是一个，就是services-config.xml，只是在services-config.xml中，包含其它三个。

在services-config.xml文件中，加入如下：
        <channel-definition id="my-streaming-amf" class="mx.messaging.channels.StreamingAMFChannel">
            <endpoint url="http://{server.name}:{server.port}/{context.root}/messagebroker/streamingamf" class="flex.messaging.endpoints.StreamingAMFEndpoint"/>
            <properties>
                <idle-timeout-minutes>0</idle-timeout-minutes>
                <max-streaming-clients>10</max-streaming-clients>
                <server-to-client-heartbeat-millis>5000</server-to-client-heartbeat-millis>
                <user-agent-settings>
                    <user-agent match-on="MSIE" kickstart-bytes="2048" max-streaming-connections-per-session="1"/>
                    <user-agent match-on="Firefox" kickstart-bytes="2048" max-streaming-connections-per-session="1"/>
                </user-agent-settings>
            </properties>
        </channel-definition>

messaging-config.xml文件中，加入如下：
    <destination id="tick-data-feed">
        <properties>
            <server>
                <allow-subtopics>true</allow-subtopics>
                <subtopic-separator>.</subtopic-separator>
            </server>
        </properties>
        <channels>
            <channel ref="my-polling-amf" />
            <channel ref="my-streaming-amf" />
        </channels>
    </destination>

Tick.as文件内容如下：
//Tick.as
package
    {
    [RemoteClass(alias="test.Tick")]
    [Bindable]
    public class Tick
    {        
        public var askPrice:Number;
        public var bidPrice:Number;
        public var midPrice:Number;
        public var tickTime:Date;;
        public var seqno:String;
    }
    
}

再在main.mxml文件中，加入如下代码：

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" viewSourceURL="srcview/index.html" height="378" width="426">

    <mx:Script>
        <![CDATA[
            import mx.controls.Alert;
            import mx.rpc.events.ResultEvent;
            import mx.rpc.events.FaultEvent;
            import mx.messaging.Consumer;
            import mx.messaging.Channel;
            import mx.messaging.ChannelSet;
            import mx.messaging.events.MessageEvent;
            
            [Bindable]
            public var tick:Tick;
            public function postUrl():void {
//             
//             httpservice.url = "http://localhost:8080/test/servlet/TickServlet?cmd=start&uid="+telId.text;
//                httpservice.send();
//                httpservice.addEventListener(ResultEvent.RESULT,resultHandler);
//                httpservice.addEventListener(FaultEvent.FAULT,faultHandler);
         user.Test(telId.text);
            }
            public function resultHandler(event:ResultEvent):void{
                submsg();
              }
            public function faultHandler(event:FaultEvent):void{
                trace(event.fault);
              }
            public function submsg():void
            {  
              
                var consumer:Consumer = new Consumer();
                consumer.destination = "tick-data-feed";
                consumer.subtopic = "tick"+telId.text;
                consumer.channelSet = new ChannelSet(["my-streaming-amf"]);
                consumer.addEventListener(MessageEvent.MESSAGE, messageHandler);
                consumer.subscribe();
            }
            
            private function messageHandler(event:MessageEvent):void 
            {

                 tick = event.message.body as Tick;
             
                txtTick.text = tick.seqno;
            }
            private function stop():void {
             user.stop(telId.text);
            }
        ]]>
    </mx:Script>

    //RemoteObject 的方式远程调用java类 userService在rremoting-config.xml中配置
    <mx:RemoteObject id="user" destination="userService" source="userService" result="resultHandler(event)"/>
    <mx:HTTPService id="httpservice" />
    <mx:Panel x="32" y="43" width="362" height="302" layout="absolute" title="Watch Tick">
        <mx:Label x="72" y="43" text="Label" id="txtTick"/>
        <mx:Button x="132" y="41" label="start" click="postUrl(); "/>
        <mx:TextInput  id="telId"  x="37" y="83"/>//标识用户
        <mx:Button label="stop" click="stop();" x="216" y="41"/>
    </mx:Panel>
</mx:Application>