ActiveMQ在C#中的应用

ActiveMQ是个好东东，不必多说。ActiveMQ提供多种语言支持，如Java, C, C++, C#, Ruby, Perl, Python, PHP等。由于我在windows下开发GUI，比较关心C++和C#，其中C#的ActiveMQ很简单，Apache提供NMS（.Net Messaging Service）支持.Net开发，只需如下几个步骤即能建立简单的实现。C++的应用相对麻烦些，稍后写文章介绍。

1、去ActiveMQ官方网站下载最新版的ActiveMQ，网址：http://activemq.apache.org/download.html。我之前下的是5.3.1，5.3.2现在也已经出来了。

2、去ActiveMQ官方网站下载最新版的Apache.NMS，网址：http://activemq.apache.org/nms/download.html，需要下载Apache.NMS和Apache.NMS.ActiveMQ两个bin包，如果对源码感兴趣，也可下载src包。这里要提醒一下，如果下载1.2.0版本的NMS.ActiveMQ，Apache.NMS.ActiveMQ.dll在实际使用中有个bug，即停止ActiveMQ应用时会抛WaitOne函数异常，查看src包中的源码发现是由于Apache.NMS.ActiveMQ-1.2.0-src\src\main\csharp\Transport\InactivityMonitor.cs中的如下代码造成的，修改一下源码重新编译即可。看了一下最新版1.3.0已经修复了这个bug，因此下载最新版即可。

view plaincopy to clipboardprint?
private void StopMonitorThreads()  
        {  
            lock(monitor)  
            {  
                if(monitorStarted.CompareAndSet(true, false))  
                {  
                    AutoResetEvent shutdownEvent = new AutoResetEvent(false);  
                    // Attempt to wait for the Timers to shutdown, but don't wait  
                    // forever, if they don't shutdown after two seconds, just quit.  
                    this.readCheckTimer.Dispose(shutdownEvent);  
                    shutdownEvent.WaitOne(TimeSpan.FromMilliseconds(2000));  
                    this.writeCheckTimer.Dispose(shutdownEvent);  
                    shutdownEvent.WaitOne(TimeSpan.FromMilliseconds(2000));  
                                                    //WaitOne的定义：public virtual bool WaitOne(TimeSpan timeout,bool exitContext)  
                    this.asyncTasks.Shutdown();  
                    this.asyncTasks = null;  
                    this.asyncWriteTask = null;  
                    this.asyncErrorTask = null;  
                }  
            }  
        } 
private void StopMonitorThreads()
        {
            lock(monitor)
            {
                if(monitorStarted.CompareAndSet(true, false))
                {
                    AutoResetEvent shutdownEvent = new AutoResetEvent(false);

                    // Attempt to wait for the Timers to shutdown, but don't wait
                    // forever, if they don't shutdown after two seconds, just quit.
                    this.readCheckTimer.Dispose(shutdownEvent);
                    shutdownEvent.WaitOne(TimeSpan.FromMilliseconds(2000));
                    this.writeCheckTimer.Dispose(shutdownEvent);
                    shutdownEvent.WaitOne(TimeSpan.FromMilliseconds(2000));
                                                    //WaitOne的定义：public virtual bool WaitOne(TimeSpan timeout,bool exitContext)
                    this.asyncTasks.Shutdown();
                    this.asyncTasks = null;
                    this.asyncWriteTask = null;
                    this.asyncErrorTask = null;
                }
            }
        }

3、运行ActiveMQ，找到ActiveMQ解压后的bin文件夹：...\apache-activemq-5.3.1\bin，执行activemq.bat批处理文件即可启动ActiveMQ服务器，默认端口为61616，这可在配置文件中修改。

4、写C#程序实现ActiveMQ的简单应用。新建C#工程（一个Producter项目和一个Consumer项目），WinForm或Console程序均可，这里建的是Console工程，添加对Apache.NMS.dll和Apache.NMS.ActiveMQ.dll的引用，然后即可编写实现代码了，简单的Producer和Consumer实现代码如下：

producer：

view plaincopy to clipboardprint?
using System;  
using System.Collections.Generic;  
using System.Text;  
using Apache.NMS;  
using Apache.NMS.ActiveMQ;  
using System.IO;  
using System.Xml.Serialization;  
using System.Runtime.Serialization.Formatters.Binary;  
namespace Publish  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            try 
            {  
                //Create the Connection Factory  
                IConnectionFactory factory = new ConnectionFactory("tcp://localhost:61616/");  
                using (IConnection connection = factory.CreateConnection())  
                {  
                    //Create the Session  
                    using (ISession session = connection.CreateSession())  
                    {  
                        //Create the Producer for the topic/queue  
                        IMessageProducer prod = session.CreateProducer(  
                            new Apache.NMS.ActiveMQ.Commands.ActiveMQTopic("testing"));  
                        //Send Messages  
                        int i = 0;  
                        while (!Console.KeyAvailable)  
                        {  
                            ITextMessage msg = prod.CreateTextMessage();  
                            msg.Text = i.ToString();  
                            Console.WriteLine("Sending: " + i.ToString());  
                            prod.Send(msg, Apache.NMS.MsgDeliveryMode.NonPersistent, Apache.NMS.MsgPriority.Normal, TimeSpan.MinValue);  
                            System.Threading.Thread.Sleep(5000);  
                            i++;  
                        }  
                    }  
                }  
                Console.ReadLine();  
           }  
            catch (System.Exception e)  
            {  
                Console.WriteLine("{0}",e.Message);  
                Console.ReadLine();  
            }  
        }  
    }  
} 
using System;
using System.Collections.Generic;
using System.Text;
using Apache.NMS;
using Apache.NMS.ActiveMQ;
using System.IO;
using System.Xml.Serialization;
using System.Runtime.Serialization.Formatters.Binary;

namespace Publish
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                //Create the Connection Factory
                IConnectionFactory factory = new ConnectionFactory("tcp://localhost:61616/");
                using (IConnection connection = factory.CreateConnection())
                {
                    //Create the Session
                    using (ISession session = connection.CreateSession())
                    {
                        //Create the Producer for the topic/queue
                        IMessageProducer prod = session.CreateProducer(
                            new Apache.NMS.ActiveMQ.Commands.ActiveMQTopic("testing"));
                        //Send Messages
                        int i = 0;

                        while (!Console.KeyAvailable)
                        {
                            ITextMessage msg = prod.CreateTextMessage();
                            msg.Text = i.ToString();
                            Console.WriteLine("Sending: " + i.ToString());
                            prod.Send(msg, Apache.NMS.MsgDeliveryMode.NonPersistent, Apache.NMS.MsgPriority.Normal, TimeSpan.MinValue);

                            System.Threading.Thread.Sleep(5000);
                            i++;
                        }
                    }
                }

                Console.ReadLine();
           }
            catch (System.Exception e)
            {
                Console.WriteLine("{0}",e.Message);
                Console.ReadLine();
            }
        }
    }
}

consumer:

view plaincopy to clipboardprint?
using System;  
using System.Collections.Generic;  
using System.Text;  
using Apache.NMS;  
using Apache.NMS.ActiveMQ;  
using System.IO;  
using System.Xml.Serialization;  
using System.Runtime.Serialization.Formatters.Binary;  
namespace Subscribe  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            try 
            {  
                //Create the Connection factory  
                IConnectionFactory factory = new ConnectionFactory("tcp://localhost:61616/");  
                //Create the connection  
                using (IConnection connection = factory.CreateConnection())  
                {  
                    connection.ClientId = "testing listener";  
                    connection.Start();  
                    //Create the Session  
                    using (ISession session = connection.CreateSession())  
                    {  
                        //Create the Consumer  
                        IMessageConsumer consumer = session.CreateDurableConsumer(new Apache.NMS.ActiveMQ.Commands.ActiveMQTopic("testing"), "testing listener", null, false);  
                        consumer.Listener += new MessageListener(consumer_Listener);  
                        Console.ReadLine();  
                    }  
                    connection.Stop();  
                    connection.Close();  
                }  
            }  
            catch (System.Exception e)  
            {  
                Console.WriteLine(e.Message);  
            }  
        }  
        static void consumer_Listener(IMessage message)  
        {  
            try 
            {  
                ITextMessage msg = (ITextMessage)message;  
                Console.WriteLine("Receive: " + msg.Text);  
           }  
            catch (System.Exception e)  
            {  
                Console.WriteLine(e.Message);  
            }  
        }  
    }  
} 
using System;
using System.Collections.Generic;
using System.Text;
using Apache.NMS;
using Apache.NMS.ActiveMQ;
using System.IO;
using System.Xml.Serialization;
using System.Runtime.Serialization.Formatters.Binary;

namespace Subscribe
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                //Create the Connection factory
                IConnectionFactory factory = new ConnectionFactory("tcp://localhost:61616/");
                //Create the connection
                using (IConnection connection = factory.CreateConnection())
                {
                    connection.ClientId = "testing listener";
                    connection.Start();

                    //Create the Session
                    using (ISession session = connection.CreateSession())
                    {
                        //Create the Consumer
                        IMessageConsumer consumer = session.CreateDurableConsumer(new Apache.NMS.ActiveMQ.Commands.ActiveMQTopic("testing"), "testing listener", null, false);
                        consumer.Listener += new MessageListener(consumer_Listener);

                        Console.ReadLine();
                    }
                    connection.Stop();
                    connection.Close();
                }
            }
            catch (System.Exception e)
            {
                Console.WriteLine(e.Message);
            }
        }

        static void consumer_Listener(IMessage message)
        {
            try
            {
                ITextMessage msg = (ITextMessage)message;
                Console.WriteLine("Receive: " + msg.Text);
           }
            catch (System.Exception e)
            {
                Console.WriteLine(e.Message);
            }
        }
    }
}

程序实现的功能：生产者producer建立名为testing的主题，并每隔5秒向该主题发送消息，消费者consumer订阅了testing主题，因此只要生产者发送testing主题的消息到ActiveMQ服务器，服务器就将该消息发送给订阅了testing主题的消费者。

编译生成producer.exe和consumer.exe，并执行两个exe，即可看到消息的发送与接收了。

这个例子是建的主题（Topic），ActiveMQ还支持另一种方式：Queue，即P2P，两者有什么区别呢？区别在于，Topic是广播，即如果某个Topic被多个消费者订阅，那么只要有消息到达服务器，服务器就将该消息发给全部的消费者；而Queue是点到点，即一个消息只能发给一个消费者，如果某个Queue被多个消费者订阅，没有特殊情况的话消息会一个一个地轮流发给不同的消费者，比如：

msg1-->consumer A

msg2-->consumer B

msg3-->consumer C

msg4-->consumer A

msg5-->consumer B

msg6-->consumer C

特殊情况是指：ActiveMQ支持过滤机制，即生产者可以设置消息的属性（Properties），该属性与消费者端的Selector对应，只有消费者设置的selector与消息的Properties匹配，消息才会发给该消费者。Topic和Queue都支持Selector。

Properties和Selector该如何设置呢？请看如下代码：

producer：

view plaincopy to clipboardprint?
ITextMessage msg = prod.CreateTextMessage();  
                            msg.Text = i.ToString();  
                            msg.Properties.SetString("myFilter", "test1");  
                            Console.WriteLine("Sending: " + i.ToString());  
                            prod.Send(msg, Apache.NMS.MsgDeliveryMode.NonPersistent, Apache.NMS.MsgPriority.Normal, TimeSpan.MinValue); 
ITextMessage msg = prod.CreateTextMessage();
                            msg.Text = i.ToString();
                            msg.Properties.SetString("myFilter", "test1");
                            Console.WriteLine("Sending: " + i.ToString());
                            prod.Send(msg, Apache.NMS.MsgDeliveryMode.NonPersistent, Apache.NMS.MsgPriority.Normal, TimeSpan.MinValue);

consumer：

view plaincopy to clipboardprint?
//生成consumer时通过参数设置Selector  
IMessageConsumer consumer = session.CreateConsumer(new Apache.NMS.ActiveMQ.Commands.ActiveMQQueue("testing"), "myFilter='test1'"); 
//生成consumer时通过参数设置Selector
IMessageConsumer consumer = session.CreateConsumer(new Apache.NMS.ActiveMQ.Commands.ActiveMQQueue("testing"), "myFilter='test1'");

 

本文来自CSDN博客，出处：http://blog.csdn.net/bodybo/archive/2010/06/04/5647968.aspx