Activemq+spring整合

activemq与spring的整合需要用到线程池。考虑到连接、会话等资源的建立和释放，无须人工操作，全部交给容器来处理。这里通过一个实例讲解activemq与spring如何整合。项目大致是这样的设计：通过jetty构建一个http请求，接收http://localhost:8080/send?msg=xxx的请求，然后将msg作为消息传递给生产者线程，将消息发送到指定的Queue，这里发送消息基本完成，为了验证接收消息，这里配置一个消费者，用来监听实时消息，而不是通过循环来读取消息，因此需要注册一个消息监听器，来监听生产者发送的消息，然后将接收的消息打印出来，完成activemq与spring整合之后发送接收的测试。

1、构建maven项目，并引入依赖库。项目最终项目结构如下：

pom.xml文件如下：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">  <modelVersion>4.0.0</modelVersion>  <groupId>com.xxx.activemq</groupId>  <artifactId>sendmessage</artifactId>  <version>0.0.1-SNAPSHOT</version>  <packaging>jar</packaging>  <name>sendmessage</name>  <url>http://maven.apache.org</url>  <properties>    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>    <spring-version>4.3.4.RELEASE</spring-version>  </properties>  <dependencies>       <dependency>              <groupId>org.eclipse.jetty</groupId>              <artifactId>test-jetty-servlet</artifactId>              <version>8.1.0.RC5</version>        </dependency>       <dependency>         <groupId>log4j</groupId>         <artifactId>log4j</artifactId>         <version>1.2.17</version>   </dependency>   <dependency>         <groupId>org.slf4j</groupId>         <artifactId>slf4j-log4j12</artifactId>         <version>1.7.21</version>   </dependency>       <dependency>         <groupId>commons-lang</groupId>         <artifactId>commons-lang</artifactId>         <version>2.6</version>    </dependency>    <dependency>        <groupId>org.apache.commons</groupId>        <artifactId>commons-pool2</artifactId>        <version>2.4.2</version>    </dependency>       <dependency>              <groupId>org.apache.activemq</groupId>              <artifactId>activemq-all</artifactId>              <version>5.15.0</version>       </dependency>       <dependency>              <groupId>org.springframework</groupId>              <artifactId>spring-beans</artifactId>              <version>${spring-version}</version>       </dependency>       <dependency>              <groupId>org.springframework</groupId>              <artifactId>spring-context</artifactId>              <version>${spring-version}</version>       </dependency>       <dependency>              <groupId>org.springframework</groupId>              <artifactId>spring-jms</artifactId>              <version>${spring-version}</version>       </dependency>  </dependencies></project>

2、主要用到的类介绍

ISendService.java

package com.xxx.activemq.service;public interface ISendService {public void send(String msg);}

SendService.java,将/send?msg=xxx发送过来的msg参数作为消息发送给activemq的一个Queue,这里是brokerQueue,后面的applicationContext.xml配置文件中会配置该Queue。

package com.xxx.activemq.service;import javax.jms.JMSException;import javax.jms.Message;import javax.jms.Session;import org.apache.log4j.Logger;import org.springframework.jms.core.JmsTemplate;import org.springframework.jms.core.MessageCreator;import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;public class SendService implements ISendService{private static final Logger LOG = Logger.getLogger(SendService.class);private String queueName;private JmsTemplate jmsTemplate;private ThreadPoolTaskExecutor threadExecutor;@Overridepublic void send(String msg) {threadExecutor.execute(new Runnable() {@Overridepublic void run() {jmsTemplate.send(queueName,new MessageCreator() {@Overridepublic Message createMessage(Session session) throws JMSException {return session.createTextMessage(msg);}});LOG.info(String.format("send msg %s to "+queueName+" ok.", msg));}});}public String getQueueName() {return queueName;}public void setQueueName(String queueName) {this.queueName = queueName;}public JmsTemplate getJmsTemplate() {return jmsTemplate;}public void setJmsTemplate(JmsTemplate jmsTemplate) {this.jmsTemplate = jmsTemplate;}public ThreadPoolTaskExecutor getThreadExecutor() {return threadExecutor;}public void setThreadExecutor(ThreadPoolTaskExecutor threadExecutor) {this.threadExecutor = threadExecutor;}}

SendServlet.java，负责处理/send?msg=xxx请求的Servlet。

package com.xxx.activemq.servlet;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.xxx.activemq.service.SendService;import com.xxx.activemq.utils.WebContext;public class SendServlet extends HttpServlet{/** *  */private static final long serialVersionUID = 1L;private static SendService sendService;static{sendService = (SendService)WebContext.getBean("sendService");}@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse res)throws ServletException, IOException {doPost(req, res);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse res)throws ServletException, IOException {String message = req.getParameter("msg");sendService.send(message);res.setCharacterEncoding("UTF-8");res.setContentType("application/json");res.setStatus(HttpServletResponse.SC_OK);res.getWriter().println("{\"message\":\"ok\"}");}}

App.java,程序入口，这里会利用jetty,构建一个http的服务，监听8080端口,然后添加handler，接收来自http://localhost:8080/send?msg=xxx的请求。

package com.xxx.activemq.webapp;import org.apache.log4j.Logger;import org.eclipse.jetty.server.Server;import org.eclipse.jetty.servlet.ServletContextHandler;import org.eclipse.jetty.servlet.ServletHolder;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.xxx.activemq.servlet.SendServlet;import com.xxx.activemq.utils.WebContext;public class App {private static final int PORT = 8080;private static final Logger LOG = Logger.getLogger(App.class);public static void main(String[] args) {ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");WebContext.setContext(context);Server server = new Server(PORT);ServletContextHandler handler = new ServletContextHandler(ServletContextHandler.SESSIONS);handler.setContextPath("/");handler.addServlet(new ServletHolder(new SendServlet()), "/send");server.setHandler(handler);try {LOG.info("webapp initialize success!");server.start();server.join();} catch (Exception e) {LOG.error("webapp initialize error!");}}}

WebContext.java,工具类，利用spring容器中定义的bean来创建bean实例。

package com.xxx.activemq.utils;import org.apache.log4j.Logger;import org.springframework.beans.BeansException;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;public class WebContext implements ApplicationContextAware {private static final Logger LOG = Logger.getLogger(WebContext.class);private static ApplicationContext context;public void setApplicationContext(ApplicationContext context)throws BeansException {LOG.info("applicationContext init...");setContext(context);}public static void setContext(ApplicationContext context) {WebContext.context = context;}public static Object getBean(String name){if(context==null){LOG.error("context is null");return null;}return context.getBean(name);}}

ConsumerMessageListener.java,这个类用来接收消息，接收SendService.java中发送的消息，这个实时接收消息。

package com.xxx.activemq.listener;import javax.jms.JMSException;import javax.jms.Message;import javax.jms.MessageListener;import javax.jms.TextMessage;import org.apache.log4j.Logger;public class ConsumerMessageListener implements MessageListener {private static Logger LOG = Logger.getLogger(ConsumerMessageListener.class);@Overridepublic void onMessage(Message msg) {if(msg instanceof TextMessage){TextMessage o = (TextMessage)msg;try {LOG.info("received message: " + o.getText());} catch (JMSException e) {LOG.error("received message for error!");}}}}

配置文件：

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd">            <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">           <property name="locations">               <list>                     <value>classpath:config.properties</value>               </list>           </property>      </bean>                     <bean id="jmsConnectionFactory" class="org.apache.activemq.pool.PooledConnectionFactory" destroy-method="stop">             <property name="connectionFactory">                   <bean class="org.apache.activemq.ActiveMQConnectionFactory">            <property name="brokerURL" value="${activemq.brokerURL}"></property>            <property name="useAsyncSend" value="true"/>            <property name="redeliveryPolicy">                 <bean class="org.apache.activemq.RedeliveryPolicy">                       <property name="initialRedeliveryDelay" value="2000"/>                       <property name="useExponentialBackOff" value="true"/>                 </bean>            </property>                 </bean>              </property>      </bean>             <bean id="connectionFactory" class="org.springframework.jms.connection.SingleConnectionFactory"> <property name="targetConnectionFactory" ref="jmsConnectionFactory"/>  </bean>       <bean id="jmsTemplate" class="org.springframework.jms.core.JmsTemplate">             <property name="connectionFactory" ref="connectionFactory"/>      </bean>      <bean id="threadExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">            <property name="corePoolSize" value="${sendmsgspool.poolsize}" />    <property name="keepAliveSeconds" value="${sendmsgspool.keepaliveseconds}" />    <property name="maxPoolSize" value="${sendmsgspool.maxpoolsize}" />    <property name="rejectedExecutionHandler">  <bean class="java.util.concurrent.ThreadPoolExecutor$DiscardOldestPolicy" />  </property>      </bean>      <bean id="sendService" class="com.xxx.activemq.service.SendService">           <property name="queueName" value="brokerQueue" />           <property name="jmsTemplate" ref="jmsTemplate"/>           <property name="threadExecutor" ref="threadExecutor"/>      </bean>       <!-- 发送消息以上这些配置足够了 -->      <!-- 下面配置收消息的消费者 -->           <bean id="consumerMessageListener" class="com.xxx.activemq.listener.ConsumerMessageListener">           </bean>      <bean id="brokerQueue" class="org.apache.activemq.command.ActiveMQQueue">            <constructor-arg value="${activemq.brokerQueue}"/>      </bean>      <bean id="jmsContainer" class="org.springframework.jms.listener.DefaultMessageListenerContainer">            <property name="connectionFactory" ref="connectionFactory"/>            <property name="messageListener" ref="consumerMessageListener"/>            <property name="destination" ref="brokerQueue"/>      </bean></beans>

config.properties ,指定brokerURL及队列名发送消息线程池信息。

activemq.brokerURL=tcp://localhost:61616activemq.brokerQueue=brokerQueuesendmsgspool.keepaliveseconds=300sendmsgspool.maxpoolsize=50sendmsgspool.poolsize=15

log4j.xml(略)

3、启动App.java，监听8080端口，接收http://localhost:8080/send?msg=xxx的请求，然后将参数msg作为消息利用生产者发送给消息接收者。

项目启动成功日志：

第一次请求：

控制台日志：

第二次请求：

控制台日志：

管理界面查看队列消息：

4、这里重要的就是要理清jmsTemplate,jmsContainer,connectionFactory,jmsConnectionFactory之间的关系。

activemq与spring的整合和java直接编写activemq实例最大的区别在于，connection,session等资源的创建和释放无需人为操作，看不到很直观的API调用。