ActiveMQ简述
lizengkui
8年前
<p> </p> <h2>概述</h2> <p>ActiveMQ是Apache所提供的一个开源的消息系统，完全采用 Java 来实现，因此，它能很好地支持J2EE提出的JMS（Java Message Service,即Java消息服务）规范。JMS是一组Java应用程序接口，它提供消息的创建、发送、读取等一系列服务。JMS提供了一组公共应用程序接口和响应的语法，类似于Java 数据库 的统一访问接口JDBC,它是一种与厂商无关的API，使得Java程序能够与不同厂商的消息组件很好地进行通信。</p> <p>JMS支持两种消息发送和接收模型。一种称为P2P(Ponit to Point)模型，即采用点对点的方式发送消息。P2P模型是基于队列的，消息生产者发送消息到队列，消息消费者从队列中接收消息，队列的存在使得消息的异步传输称为可能，P2P模型在点对点的情况下进行消息传递时采用。</p> <p><img src="https://simg.open-open.com/show/69ba35a5cabf03f8068b64a20661cee4.png"></p> <p>另一种称为Pub/Sub(Publish/Subscribe，即发布-订阅)模型，发布-订阅模型定义了如何向一个内容节点发布和订阅消息，这个内容节点称为topic(主题)。主题可以认为是消息传递的中介，消息发布这将消息发布到某个主题，而消息订阅者则从主题订阅消息。主题使得消息的订阅者与消息的发布者互相保持独立，不需要进行接触即可保证消息的传递，发布-订阅模型在消息的一对多广播时采用。</p> <p><img src="https://simg.open-open.com/show/88c5c4c82535b18704f3a63fd1513a90.png"></p> <h2>ActiveMQ的安装</h2> <p>下载最新的安装包apache-activemq-5.13.2-bin.tar.gz（此包linux下的，案例也是针对linux系统进行阐述，当然ActiveMQ也有win版的，这里就不赘述了），可以去 <a href="/misc/goto?guid=4958323481424978975" rel="nofollow,noindex">官网</a> 下载，也可以在下方留言区留下你的邮箱，博主会发给你的~</p> <p>下载之后解压： tar -zvxf apache-activemq-5.13.2-bin.tar.gz</p> <p>ActiveMQ目录内容有：</p> <ul> <li>bin目录包含ActiveMQ的启动脚本</li> <li>conf目录包含ActiveMQ的所有配置文件</li> <li>data目录包含日志文件和持久性消息数据</li> <li>example: ActiveMQ的示例</li> <li>lib: ActiveMQ运行所需要的lib</li> <li>webapps: ActiveMQ的web控制台和一些相关的demo</li> </ul> <p>运行命令： <strong>activemq start</strong> （在activemq/bin下运行）</p> <pre> <code>INFO: Loading '/users/shr/apache-activemq-5.13.2//bin/env' INFO: Using java '/users/shr/util/JavaDir/jdk/bin/java' INFO: Starting - inspect logfiles specified in logging.properties and log4j.properties to get details INFO: pidfile created : '/users/shr/apache-activemq-5.13.2//data/activemq.pid' (pid '986')</code></pre> <p>查看activemq是否运行命令： <strong>ps -aux | grep activemq</strong></p> <pre> <code>shr 986 1.2 9.7 1281720 201936 pts/5 Sl 19:43 0:17 /users/shr/util/JavaDir/jdk/bin/java -Xms64M -Xmx1G -Djava.util.logging.config.file=logging.properties -Djava.security.auth.login.config=/users/shr/apache-activemq-5.13.2//conf/login.config -Dcom.sun.management.jmxremote -Djava.awt.headless=true -Djava.io.tmpdir=/users/shr/apache-activemq-5.13.2//tmp -Dactivemq.classpath=/users/shr/apache-activemq-5.13.2//conf:/users/shr/apache-activemq-5.13.2//../lib/: -Dactivemq.home=/users/shr/apache-activemq-5.13.2/ -Dactivemq.base=/users/shr/apache-activemq-5.13.2/ -Dactivemq.conf=/users/shr/apache-activemq-5.13.2//conf -Dactivemq.data=/users/shr/apache-activemq-5.13.2//data -jar /users/shr/apache-activemq-5.13.2//bin/activemq.jar start shr 1501 0.0 0.0 5176 724 pts/5 S+ 20:06 0:00 grep activemq</code></pre> <p>关闭命令： <strong>activemq stop</strong></p> <pre> <code>INFO: Loading '/users/shr/apache-activemq-5.13.2//bin/env' INFO: Using java '/users/shr/util/JavaDir/jdk/bin/java' INFO: Waiting at least 30 seconds for regular process termination of pid '986' : Java Runtime: Oracle Corporation 1.7.0_79 /users/shr/util/JavaDir/jdk1.7.0_79/jre Heap sizes: current=63232k free=62218k max=932096k JVM args: -Xms64M -Xmx1G -Djava.util.logging.config.file=logging.properties -Djava.security.auth.login.config=/users/shr/apache-activemq-5.13.2//conf/login.config -Dactivemq.classpath=/users/shr/apache-activemq-5.13.2//conf:/users/shr/apache-activemq-5.13.2//../lib/: -Dactivemq.home=/users/shr/apache-activemq-5.13.2/ -Dactivemq.base=/users/shr/apache-activemq-5.13.2/ -Dactivemq.conf=/users/shr/apache-activemq-5.13.2//conf -Dactivemq.data=/users/shr/apache-activemq-5.13.2//data Extensions classpath: [/users/shr/apache-activemq-5.13.2/lib,/users/shr/apache-activemq-5.13.2/lib/camel,/users/shr/apache-activemq-5.13.2/lib/optional,/users/shr/apache-activemq-5.13.2/lib/web,/users/shr/apache-activemq-5.13.2/lib/extra] ACTIVEMQ_HOME: /users/shr/apache-activemq-5.13.2 ACTIVEMQ_BASE: /users/shr/apache-activemq-5.13.2 ACTIVEMQ_CONF: /users/shr/apache-activemq-5.13.2/conf ACTIVEMQ_DATA: /users/shr/apache-activemq-5.13.2/data Connecting to pid: 986 ..Stopping broker: localhost .. TERMINATED</code></pre> <p>ActiveMQ的默认服务端口为61616，这个可以在conf/activemq.xml配置文件中修改：</p> <pre> <code class="language-xml"><transportConnectors> <!-- DOS protection, limit concurrent connections to 1000 and frame size to 100MB --> <transportConnector name="openwire" uri="tcp://0.0.0.0:61616?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/> </transportConnectors></code></pre> <p>在下载的apache-activemq-5.13.2-bin.tar.gz包中解压有一个jar包：activemq-all-5.13.2.jar，引入这个jar到你的项目中即可开始编写案例代码。</p> <p>博主的activemq服务器地址为10.10.195.187，这个在下面代码中会有体现。</p> <p>按照JMS的规范，我们首先需要获得一个JMS connection factory.，通过这个connection factory来创建connection.在这个基础之上我们再创建session, destination, producer和consumer。因此主要的几个步骤如下：</p> <ol> <li>获得JMS connection factory. 通过我们提供特定环境的连接信息来构造factory。</li> <li>利用factory构造JMS connection</li> <li>启动connection</li> <li>通过connection创建JMS session.</li> <li>指定JMS destination.</li> <li>创建JMS producer或者创建JMS message并提供destination.</li> <li>创建JMS consumer或注册JMS message listener.</li> <li>发送和接收JMS message.</li> <li>关闭所有JMS资源，包括connection, session, producer, consumer等。</li> </ol> <p>下面来看代码举例（P2P式）。通过Java实现的基于ActiveMQ的请求提交：</p> <pre> <code class="language-java">package com.zzh.activemq; import java.io.Serializable; import java.util.HashMap; import javax.jms.Connection; import javax.jms.ConnectionFactory; import javax.jms.DeliveryMode; import javax.jms.Destination; import javax.jms.MessageProducer; import javax.jms.ObjectMessage; import javax.jms.Session; import org.apache.activemq.ActiveMQConnection; import org.apache.activemq.ActiveMQConnectionFactory; public class RequestSubmit { //消息发送者 private MessageProducer producer; //一个发送或者接受消息的线程 private Session session; public void init() throws Exception { //ConnectionFactory连接工厂，JMS用它创建连接 ConnectionFactory connectionFactory = new ActiveMQConnectionFactory( ActiveMQConnection.DEFAULT_USER, ActiveMQConnection.DEFAULT_PASSWORD, "tcp://10.10.195.187:61616"); //Connection：JMS客户端到JMS Provider的连接，从构造工厂中得到连接对象 Connection connection = connectionFactory.createConnection(); //启动 connection.start(); //获取连接操作 session = connection.createSession(Boolean.TRUE, Session.AUTO_ACKNOWLEDGE); Destination destinatin = session.createQueue("RequestQueue"); //得到消息生成（发送）者 producer = session.createProducer(destinatin); //设置不持久化 producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT); } public void submit(HashMap<Serializable,Serializable> requestParam) throws Exception { ObjectMessage message = session.createObjectMessage(requestParam); producer.send(message); session.commit(); } public static void main(String[] args) throws Exception{ RequestSubmit submit = new RequestSubmit(); submit.init(); HashMap<Serializable,Serializable> requestParam = new HashMap<Serializable,Serializable>(); requestParam.put("朱小厮", "zzh"); submit.submit(requestParam); } }</code></pre> <p>创建Session时有两个非常重要的参数，第一个boolean类型的参数用来表示是否采用事务消息。如果是事务消息，对于的参数设置为true，此时消息的提交自动有comit处理，消息的回滚则自动由rollback处理。加入消息不是事务的，则对应的该参数设置为false，此时分为三种情况：</p> <ul> <li>Session.AUTO_ACKNOWLEDGE表示Session会自动确认所接收到的消息。</li> <li>Session.CLIENT_ACKNOWLEDGE表示由客户端程序通过调用消息的确认方法来确认所接收到的消息。</li> <li>Session.DUPS_OK_ACKNOWLEDGE使得Session将“懒惰”地确认消息，即不会立即确认消息，这样有可能导致消息重复投递。</li> </ul> <p>提供Java实现的基于ActiveMQ的请求处理：</p> <pre> <code class="language-java">package com.zzh.activemq; import java.io.Serializable; import java.util.HashMap; import java.util.Map; import javax.jms.Connection; import javax.jms.ConnectionFactory; import javax.jms.Destination; import javax.jms.MessageConsumer; import javax.jms.ObjectMessage; import javax.jms.Session; import org.apache.activemq.ActiveMQConnection; import org.apache.activemq.ActiveMQConnectionFactory; public class RequestProcessor { public void requestHandler(HashMap<Serializable,Serializable> requestParam) throws Exception { System.out.println("requestHandler....."+requestParam.toString()); for(Map.Entry<Serializable, Serializable> entry : requestParam.entrySet()) { System.out.println(entry.getKey()+":"+entry.getValue()); } } public static void main(String[] args) throws Exception { ConnectionFactory connectionFactory = new ActiveMQConnectionFactory( ActiveMQConnection.DEFAULT_USER, ActiveMQConnection.DEFAULT_PASSWORD, "tcp://10.10.195.187:61616"); Connection connection = connectionFactory.createConnection(); connection.start(); Session session = connection.createSession(Boolean.FALSE, Session.AUTO_ACKNOWLEDGE); Destination destination = session.createQueue("RequestQueue"); //消息消费（接收）者 MessageConsumer consumer = session.createConsumer(destination); RequestProcessor processor = new RequestProcessor(); while(true) { ObjectMessage message = (ObjectMessage) consumer.receive(1000); if(null != message) { System.out.println(message); HashMap<Serializable,Serializable> requestParam = (HashMap<Serializable,Serializable>) message.getObject(); processor.requestHandler(requestParam); } else { break; } } } }</code></pre> <p>输出结果：</p> <pre> <code>ActiveMQObjectMessage {commandId = 6, responseRequired = false, messageId = ID:hidden-PC-58748-1460550507055-1:1:1:1:1, originalDestination = null, originalTransactionId = null, producerId = ID:hidden-PC-58748-1460550507055-1:1:1:1, destination = queue://RequestQueue, transactionId = TX:ID:hidden-PC-58748-1460550507055-1:1:1, expiration = 0, timestamp = 1460550507333, arrival = 0, brokerInTime = 1460550505969, brokerOutTime = 1460550509143, correlationId = null, replyTo = null, persistent = false, type = null, priority = 4, groupID = null, groupSequence = 0, targetConsumerId = null, compressed = false, userID = null, content = org.apache.activemq.util.ByteSequence@74a456bb, marshalledProperties = null, dataStructure = null, redeliveryCounter = 0, size = 0, properties = null, readOnlyProperties = true, readOnlyBody = true, droppable = false, jmsXGroupFirstForConsumer = false} requestHandler.....{朱小厮=zzh} 朱小厮:zzh</code></pre> <p>可以通过页面查看队列的使用情况，在浏览器中输入 <a href="/misc/goto?guid=4959673147068340717" rel="nofollow,noindex">http://10.10.195.187:8161/admin/queues.jsp</a> ，用户名和密码都是：admin，看到以下页面：</p> <p><img src="https://simg.open-open.com/show/2b9dab18c15489376574004e60dd6ebc.png"></p> <p>这个是在jetty服务器下跑的，可以修改conf/jetty.xml来修改相关jetty配置。</p> <p>上面的例子是关于P2P模式的，不过有个不妥之处，就是没有资源的释放。下面举一个Pub/Sub模式的。通过JMS创建ActiveMQ的topic，并给topic发送消息：</p> <pre> <code class="language-java">import javax.jms.Connection; import javax.jms.ConnectionFactory; import javax.jms.DeliveryMode; import javax.jms.JMSException; import javax.jms.MessageProducer; import javax.jms.ObjectMessage; import javax.jms.Session; import javax.jms.TextMessage; import javax.jms.Topic; import org.apache.activemq.ActiveMQConnection; import org.apache.activemq.ActiveMQConnectionFactory; import org.apache.camel.Produce; public class TopicRequest { //消息发送者 private MessageProducer producer; //一个发送或者接受消息的线程 private Session session; //Connection：JMS客户端到JMS Provider的连接 private Connection connection; public void init() throws Exception { //ConnectionFactory连接工厂，JMS用它创建连接 ConnectionFactory connectionFactory = new ActiveMQConnectionFactory( ActiveMQConnection.DEFAULT_USER, ActiveMQConnection.DEFAULT_PASSWORD, "tcp://10.10.195.187:61616"); //从构造工厂中得到连接对象 connection = connectionFactory.createConnection(); //启动 connection.start(); //获取连接操作 session = connection.createSession(Boolean.FALSE, Session.AUTO_ACKNOWLEDGE); Topic topic = session.createTopic("MessageTopic"); producer = session.createProducer(topic); //设置不持久化 producer.setDeliveryMode(DeliveryMode.NON_PERSISTENT); } public void submit(String mess) throws Exception { TextMessage message = session.createTextMessage(); message.setText(mess); producer.send(message); } public void close() { try { if(session != null) session.close(); if(producer != null) producer.close(); if(connection !=null ) connection.close(); } catch (JMSException e) { e.printStackTrace(); } } public static void main(String[] args) throws Exception { TopicRequest topicRequest = new TopicRequest(); topicRequest.init(); topicRequest.submit("I'm first"); topicRequest.close(); } }</code></pre> <p>消息发送到对应的topic后，需要将listener注册到需要订阅的topic上，以便能够接收该topic的消息：</p> <pre> <code class="language-java">import javax.jms.Connection; import javax.jms.ConnectionFactory; import javax.jms.JMSException; import javax.jms.Message; import javax.jms.MessageConsumer; import javax.jms.MessageListener; import javax.jms.Session; import javax.jms.TextMessage; import javax.jms.Topic; import org.apache.activemq.ActiveMQConnection; import org.apache.activemq.ActiveMQConnectionFactory; public class TopicReceive { private MessageConsumer consumer; private Session session; public void init() throws Exception { ConnectionFactory connectionFactory = new ActiveMQConnectionFactory( ActiveMQConnection.DEFAULT_USER, ActiveMQConnection.DEFAULT_PASSWORD, "tcp://10.10.195.187:61616"); Connection connection = connectionFactory.createConnection(); connection.start(); session = connection.createSession(Boolean.FALSE, Session.AUTO_ACKNOWLEDGE); Topic topic = session.createTopic("MessageTopic"); consumer = session.createConsumer(topic); consumer.setMessageListener(new MessageListener(){ @Override public void onMessage(Message message) { TextMessage tm = (TextMessage) message; System.out.println(tm); try { System.out.println(tm.getText()); } catch (JMSException e) { e.printStackTrace(); } } }); } public static void main(String[] args) throws Exception { TopicReceive receive = new TopicReceive(); receive.init(); } }</code></pre> <p>输出结果：</p> <pre> <code>ActiveMQTextMessage {commandId = 5, responseRequired = false, messageId = ID:hidden-PC-50073-1460597487065-1:1:1:1:1, originalDestination = null, originalTransactionId = null, producerId = ID:hidden-PC-50073-1460597487065-1:1:1:1, destination = topic://MessageTopic, transactionId = null, expiration = 0, timestamp = 1460597487308, arrival = 0, brokerInTime = 1460597487297, brokerOutTime = 1460597487298, correlationId = null, replyTo = null, persistent = false, type = null, priority = 4, groupID = null, groupSequence = 0, targetConsumerId = null, compressed = false, userID = null, content = org.apache.activemq.util.ByteSequence@2e4d3abf, marshalledProperties = null, dataStructure = null, redeliveryCounter = 0, size = 0, properties = null, readOnlyProperties = true, readOnlyBody = true, droppable = false, jmsXGroupFirstForConsumer = false, text = I'm first} I'm first</code></pre> <p>参考文献</p> <p>1. 《大型分布式网站 <a href="/misc/goto?guid=4959673147154813799" rel="nofollow,noindex">架构</a> ——设计与实践》陈康贤著。</p> <p>2. <a href="/misc/goto?guid=4958323481424978975" rel="nofollow,noindex">http://activemq.apache.org/</a></p> <p> </p> <p>via： http://www.importnew.com/19690.html</p>