初识ActiveMQ - 码农教程

①.消息传递方式介绍:

Activemq支持两种方式的消息传递:

广播模式:1-n的方式,是一种发布订阅模式,像腾讯新闻那样,只要我们微信关注了腾讯新闻,那么每个人都会收到推送的新闻

队列模式:1-1的方式,只能有一个消费者端消费生产者生产的数据

②.消息类型介绍:

Activemq提供了两种消息类型:持久化和非持久化:

消息生产者使用持久（persistent）传递模式发送消息的时候，Producer.send() 方法会被阻塞，直到 broker 发送一个确认消息给生产者(ProducerAck)，这个确认消息暗示broker已经成功接收到消息并把消息保存到二级存储中。这个过程通常称为同步发送。速度较慢,数据基本不会丢失.可以持久化到kahaDB(aMq默认采用kahaDB存储引擎来存储消息)或数据库中

异步发送不会在受到 broker 的确认之前一直阻塞 Producer.send 方法,速度较快,不过可能会造成数据的丢失.

消息签收方式:

AUTO_ACKNOWLEDGE 自动确认

CLIENT_ACKNOWLEDGE 客户端手动确认

DUPS_OK_ACKNOWLEDGE 自动批量确认

SESSION_TRANSACTED 事务提交并确认

③.下载可以到apache activeMQ官网下载

④.我这里下载的是windows 5.10版本的就以此为例做介绍

解压之后进入bin目录根据操作系统找到对应的,activemq.bat文件双击运行

activeMQ内置有一个控制台可以访问http://localhost:8161/查看,默认账户密码皆为admin

⑤.客户端代码(java为例):

public class ActiveMqBo {
	
	// 创建连接工厂
	private ConnectionFactory  factory = new ActiveMQConnectionFactory(ActiveMqConstant.URL);
	
	/**
	 * 获取一个连接
	 * @return
	 * @throws JMSException
	 */
	public  Connection getConnection() throws JMSException {
		Connection conn;
		try {
			conn = factory.createConnection();
		} catch (JMSException e) {
			e.printStackTrace();
			throw e;
		}
		return conn;
	}
	
}

public static void main(String[] args) {
		ActiveMqBo mq = new ActiveMqBo();
		Connection conn = null;
		Session session = null;
		MessageProducer producer = null;
		try {
			// 获取一个连接
			conn = mq.getConnection();
			conn.start();
			// 签收方式
			session = conn.createSession(Boolean.FALSE, Session.AUTO_ACKNOWLEDGE);
			// 创建一个队列
			Destination destination = session.createQueue("queue-1");
			// 获取一个生产者
			producer = session.createProducer(destination);
			/*
			 * 持久化,会通过kahadb把消息存入到db.log中,直到被消费后进行清除
			 * 速度较慢
             * DeliveryMode.NON_PERSISTENT非持久化
             *  DeliveryMode.PERSISTENT持久化
			 */
			producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
			// producer.setTimeToLive(5000);//5秒后过期，这个对点对点模式有效
			for (int i = 0; i < 1000; i++) {
				MessageDto mes = new MessageDto();
				mes.setCode("" + (i + 1));
				mes.setMessage("send mes:" + (i + 1));
				producer.send(session.createObjectMessage(mes));
				System.out.println("send mes : " + mes);
			}

		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				if (producer != null) {
					producer.close();
				}
				if (session != null) {
					session.close();
				}
				if (conn != null) {
					conn.close();
				}
			} catch (JMSException e) {
				e.printStackTrace();
			}
		}
	}

日志部分:

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/D:/repository/ch/qos/logback/logback-classic/1.0.13/logback-classic-1.0.13.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/D:/repository/org/apache/activemq/activemq-all/5.10.0/activemq-all-5.10.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [ch.qos.logback.classic.util.ContextSelectorStaticBinder]
11:27:42.251 [main] DEBUG o.a.a.transport.WireFormatNegotiator - Sending: WireFormatInfo { version=10, properties={MaxFrameSize=9223372036854775807, CacheSize=1024, CacheEnabled=true, Host=127.0.0.1, SizePrefixDisabled=false, MaxInactivityDurationInitalDelay=10000, TcpNoDelayEnabled=true, MaxInactivityDuration=30000, TightEncodingEnabled=true, StackTraceEnabled=true}, magic=[A,c,t,i,v,e,M,Q]}
11:27:42.252 [ActiveMQ Transport: tcp:///127.0.0.1:61616@54559] DEBUG o.a.a.transport.WireFormatNegotiator - Received WireFormat: WireFormatInfo { version=10, properties={CacheSize=1024, MaxFrameSize=104857600, CacheEnabled=true, SizePrefixDisabled=false, TcpNoDelayEnabled=true, MaxInactivityDurationInitalDelay=10000, MaxInactivityDuration=30000, TightEncodingEnabled=true, StackTraceEnabled=true}, magic=[A,c,t,i,v,e,M,Q]}
11:27:42.257 [main] DEBUG o.a.a.transport.InactivityMonitor - Using min of local: WireFormatInfo { version=10, properties={MaxFrameSize=9223372036854775807, CacheSize=1024, CacheEnabled=true, Host=127.0.0.1, SizePrefixDisabled=false, MaxInactivityDurationInitalDelay=10000, TcpNoDelayEnabled=true, MaxInactivityDuration=30000, TightEncodingEnabled=true, StackTraceEnabled=true}, magic=[A,c,t,i,v,e,M,Q]} and remote: WireFormatInfo { version=10, properties={CacheSize=1024, MaxFrameSize=104857600, CacheEnabled=true, SizePrefixDisabled=false, TcpNoDelayEnabled=true, MaxInactivityDurationInitalDelay=10000, MaxInactivityDuration=30000, TightEncodingEnabled=true, StackTraceEnabled=true}, magic=[A,c,t,i,v,e,M,Q]}
11:27:42.260 [ActiveMQ Transport: tcp:///127.0.0.1:61616@54559] DEBUG o.a.a.transport.WireFormatNegotiator - tcp:///127.0.0.1:61616@54559 before negotiation: OpenWireFormat{version=10, cacheEnabled=false, stackTraceEnabled=false, tightEncodingEnabled=false, sizePrefixDisabled=false, maxFrameSize=9223372036854775807}
11:27:42.261 [ActiveMQ Transport: tcp:///127.0.0.1:61616@54559] DEBUG o.a.a.transport.WireFormatNegotiator - tcp:///127.0.0.1:61616@54559 after negotiation: OpenWireFormat{version=10, cacheEnabled=true, stackTraceEnabled=true, tightEncodingEnabled=true, sizePrefixDisabled=false, maxFrameSize=104857600}
send mes : MessageDto [code=1, message=send mes:1]
send mes : MessageDto [code=2, message=send mes:2]
send mes : MessageDto [code=3, message=send mes:3]
send mes : MessageDto [code=4, message=send mes:4]
send mes : MessageDto [code=5, message=send mes:5]
send mes : MessageDto [code=6, message=send mes:6]
send mes : MessageDto [code=7, message=send mes:7]
send mes : MessageDto [code=8, message=send mes:8]
........省略
send mes : MessageDto [code=996, message=send mes:996]
send mes : MessageDto [code=997, message=send mes:997]
send mes : MessageDto [code=998, message=send mes:998]
send mes : MessageDto [code=999, message=send mes:999]
send mes : MessageDto [code=1000, message=send mes:1000]
11:27:42.490 [main] DEBUG o.a.activemq.util.ThreadPoolUtils - Shutdown of ExecutorService: java.util.concurrent.ThreadPoolExecutor@2e0f6c25[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 0] is shutdown: true and terminated: true took: 0.000 seconds.
11:27:42.490 [ActiveMQ Transport: tcp:///127.0.0.1:61616@54559] DEBUG o.a.activemq.util.ThreadPoolUtils - Shutdown of ExecutorService: java.util.concurrent.ThreadPoolExecutor@768508c2[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 0] is shutdown: true and terminated: true took: 0.000 seconds.
11:27:42.491 [main] DEBUG o.a.a.transport.tcp.TcpTransport - Stopping transport tcp:///127.0.0.1:61616@54559
11:27:42.492 [main] DEBUG o.a.a.thread.TaskRunnerFactory - Initialized TaskRunnerFactory[ActiveMQ Task] using ExecutorService: java.util.concurrent.ThreadPoolExecutor@b30e9f8[Running, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 0]
11:27:42.493 [ActiveMQ Task-1] DEBUG o.a.a.transport.tcp.TcpTransport - Closed socket Socket[addr=/127.0.0.1,port=61616,localport=54559]
11:27:42.493 [main] DEBUG o.a.activemq.util.ThreadPoolUtils - Forcing shutdown of ExecutorService: java.util.concurrent.ThreadPoolExecutor@b30e9f8[Running, pool size = 1, active threads = 1, queued tasks = 0, completed tasks = 0]

这里我们再看控制台,会发现queue1有数据信息,因为我们是非持久化方式发送消息,我们关掉activemq后在重启会发现数据丢失

,再以持久化的方式测试:

只需要将这里设置为PERSISTENT即可

producer.setDeliveryMode(DeliveryMode.PERSISTENT);

我们再启动刚才的代码会发现发送数据的速度很明显的降低,但是我们关闭activemq后再重启,刷新控制台数据没有丢失.

⑥.消费端:

public class Consumer {
	
	public static void main(String[] args) {
		try {
			MessageUtil.getConsumer("queue-1", Boolean.TRUE);
        } catch (JMSException e) {
	        e.printStackTrace();
        }
    }
	
}

public class MessageUtil {
	private static ActiveMqBo mq = new ActiveMqBo();
	private static Connection conn = null;
	private static Session session = null;
	private static void init(){
		try {
			// 获取一个连接
			if(conn == null){
				conn = mq.getConnection();
			}
			conn.start();
			// 自动提交事务
			if(session == null){
				 /*Session.AUTO_ACKNOWLEDGE  消息自动签收 
                 Session.CLIENT_ACKNOWLEDGE  客戶端调用acknowledge方法手动签收 
                 Session.DUPS_OK_ACKNOWLEDGE 不是必须签收，消息可能会重复发送。在第二次重新传送消息的时候，消息 
                 	头的JmsDelivered会被置为true标示当前消息已经传送过一次，客户端需要进行消息的重复处理控制。*/
				session = conn.createSession(Boolean.FALSE, Session.AUTO_ACKNOWLEDGE);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	/**
	 * 
	 * @param obj 序列化对象
	 * @param topic
	 * @param isQueue
	 * @throws JMSException
	 */
	public static void sendObjectMessage(Serializable obj,String topic,boolean isQueue) throws JMSException{
		init();
		MessageProducer producer = getProducer(getDestination(topic, isQueue));
		producer.send(session.createObjectMessage(obj));
		destroy(producer);
	}
	
	public static void sendTextMessage(String mes,String topic,boolean isQueue) throws JMSException{
		init();
		MessageProducer producer = getProducer(getDestination(topic, isQueue));
		producer.send(session.createTextMessage(mes));
		destroy(producer);
	}
	
	private static MessageProducer getProducer(Destination destination) throws JMSException{
		MessageProducer producer = session.createProducer(destination);
		/** PERSISTENT(持久性消息):
		 *   这是ActiveMQ的默认传送模式，此模式保证这些消息只被传送一次和成功使用一次。对于这些消息，可靠性是优先考虑的因素。
		 *   可靠性的另一个重要方面是确保持久性消息传送至目标后，消息服务在向消费者传送它们之前不会丢失这些消息。这意味着在持久性消息传送至目标时，
		 *   消息服务将其放入持久性数据存储。如果消息服务由于某种原因导致失败，
		 *   它可以恢复此消息并将此消息传送至相应的消费者。虽然这样增加了消息传送的开销，但却增加了可靠性。
		 *  NON_PERSISTENT(非持久性消息):
		 *   保证这些消息最多被传送一次。对于这些消息，可靠性并非主要的考虑因素。
		 *   此模式并不要求持久性的数据存储，也不保证消息服务由于某种原因导致失败后消息不会丢失。
		 *   
		 */
		producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);
		return producer;
	}

	private static Destination getDestination(String topic, boolean isQueue) throws JMSException {
		Destination destination = null;
		if (isQueue) {
			destination = session.createQueue(topic);
		} else {
			destination = session.createTopic(topic);
		}
		return destination;
	}
	
	public static void getConsumer(String topic, boolean isQueue) throws JMSException{
		init();
		MessageConsumer consumer = session.createConsumer(getDestination(topic, isQueue));
		if(Arrays.asList(ActiveMqConstant.QUEUES).contains(topic) ||
				Arrays.asList(ActiveMqConstant.TOPICS).contains(topic) ){
			MessageListener listener = ActiveMqConstant.listeners.get(topic);
			consumer.setMessageListener(listener);
		}
	}
	
	private static void destroy(MessageProducer producer) throws JMSException{
		if(producer != null){
			producer.close();
		}
		if(session!=null){
			session.close();
			session = null;
		}
		if(conn!=null){
			conn.close();
			conn = null;
		}
	}
	public static void destroy(MessageConsumer consumer) throws JMSException{
		if(consumer != null){
			consumer.close();
			consumer = null;
		}
		if(session!=null){
			session.close();
			session = null;
		}
		if(conn!=null){
			conn.close();
			conn = null;
		}
	}

public class ActiveMqConstant {
	public static final String USERNAME = "admin", PASSWORD = "admin";
	public static final String URL = "tcp://127.0.0.1:61616";
	public static final String[] QUEUES = { "queue-1", "queue2", "queue3" };
	public static final String[] TOPICS = { "topic1", "topic2", "topic3" };
	public static Map<String, MessageListener> listeners = new LinkedHashMap<String, MessageListener>();
	static{
		init();
	}
	private static void init(){
		//后期可以从xml中配置获取
		listeners.put("queue-1",new ActiveMQMessageListener());
		listeners.put("queue2",new ActiveMQMessageListener2());
		listeners.put("queue3",new ActiveMQMessageListener3());
		
		listeners.put("topic1",new ActiveMQMessageListener());
		listeners.put("topic2",new ActiveMQMessageListener2	());
		listeners.put("topic3",new ActiveMQMessageListener3());
		
	}
	private ActiveMqConstant() {
	}

}

....省略
receiver:MessageDto [code=402, message=send mes:402]
receiver:MessageDto [code=403, message=send mes:403]
receiver:MessageDto [code=404, message=send mes:404]
...省略
receiver:MessageDto [code=2085, message=send mes:2085]
receiver:MessageDto [code=2086, message=send mes:2086]
receiver:MessageDto [code=2087, message=send mes:2087]
receiver:MessageDto [code=2088, message=send mes:2088]
receiver:MessageDto [code=2089, message=send mes:2089]
13:53:21.896 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:53:21.899 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]
13:53:31.897 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:53:31.897 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]
13:53:41.897 [ActiveMQ InactivityMonitor ReadCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - 30002ms elapsed since last read check.
13:53:41.898 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:53:41.898 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]
13:53:51.899 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:53:51.899 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]
13:54:01.900 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:54:01.901 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]
13:54:11.899 [ActiveMQ InactivityMonitor ReadCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - 30002ms elapsed since last read check.
13:54:11.901 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:54:11.901 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]
13:54:21.902 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:54:21.902 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]
13:54:31.903 [ActiveMQ InactivityMonitor WriteCheckTimer] DEBUG o.a.a.t.AbstractInactivityMonitor - WriteChecker: 10001ms elapsed since last write check.
13:54:31.903 [ActiveMQ InactivityMonitor Worker] DEBUG o.a.a.t.AbstractInactivityMonitor - Running WriteCheck[tcp://127.0.0.1:61616]

再次刷新控制台看界面变化

⑦.了解activemq的目录结构 ,会发现如下几个文件:

db.data,db.redo,db-1.log

在消息未被消费之前会将数据保存在db-*.log中, 其中activemq默认每超过32m重新生成一个新的日志文件.

db.data：存储btree索引 ,BTree索引，保存消息的引用，并按照message ID排序。 db.redo：用来保证MQ broker未干净关闭情况下，用于BTree index的重建。

注意:对于非持久化的数据如果未及时消费,当activemq宕机时,保存的db-*.log等信息在下次启动时全部丢失.

广播模式不再介绍,跟队列方式相似,可以自己多开几个consumer看接收到的内容是否一致