Spring 之 JMS 监听JMS消息

分类: 转载文章 0人评论 dexcoder 1年前发布

    在调用JMS消息消费者的receive()方法接收消息时,调用线程在消息可用之前一直阻塞。该线程出了等待还是等待,无所事事。这样的消息接收是同步消息接收,因为只用等到消息到达才能接收线程的工作。

     有同步的消息接收就有异步的消息接收,异步的消息接收就是注册一个消息监听器,该消息监听器必须实现javax.jms.MessageListener接口,当消息到达时将调用onMessage()方法,以消息作为方法的参数。

 

    原生的接口是javax.jms.MessageListener,除了这个原生的接口外,Spring 还提供了 SessionAwareMessageListener和MessageListenerAdapter.

 

/**
 *
 * @author zhangwei_david
 * @version $Id: MessageListener.java, v 0.1 2015年1月31日 下午9:06:02 zhangwei_david Exp $
 */
public class MailMessageListener implements MessageListener {
    private MessageConverter messageConverter;
    /**
     * @see javax.jms.MessageListener#onMessage(javax.jms.Message)
     */
    public void onMessage(Message msg) {
        try {
            System.out.println("on message:" + messageConverter.fromMessage(msg));
        } catch (JMSException e) {
        }
    }
    /**
     * Setter method for property <tt>messageConverter</tt>.
     *
     * @param messageConverter value to be assigned to property messageConverter
     */
    public void setMessageConverter(MessageConverter messageConverter) {
        this.messageConverter = messageConverter;
    }
}

     Spring 中提供了多种消息监听器的容器,常用的容器有SimpleMessageListenerContainer 和DefaultMessageListenerContainer。SimpleMessageListenerContainer 是一个最简单的容器,不提供事务的支持,DefaultMessageListenerContainer是默认的容器实现,支持事务。

 

/**
 *
 * @author zhangwei_david
 * @version $Id: ToStringBase.java, v 0.1 2015年2月2日 下午7:41:52 zhangwei_david Exp $
 */
public class ToStringBase {
    /**
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return ToStringBuilder.reflectionToString(this, ToStringStyle.SHORT_PREFIX_STYLE);
    }
}

 

定义一个基本的对象

/**
 *
 * @author zhangwei_david
 * @version $Id: Mail.java, v 0.1 2015年2月2日 下午7:25:24 zhangwei_david Exp $
 */
public class Mail extends ToStringBase {
    /**id**/
    private String mailId;
    private String from;
    private String to;
    private String content;
    /**
     * Getter method for property <tt>mailId</tt>.
     *
     * @return property value of mailId
     */
    public String getMailId() {
        return mailId;
    }
    /**
     * Setter method for property <tt>mailId</tt>.
     *
     * @param mailId value to be assigned to property mailId
     */
    public void setMailId(String mailId) {
        this.mailId = mailId;
    }
    /**
     * Getter method for property <tt>from</tt>.
     *
     * @return property value of from
     */
    public String getFrom() {
        return from;
    }
    /**
     * Setter method for property <tt>from</tt>.
     *
     * @param from value to be assigned to property from
     */
    public void setFrom(String from) {
        this.from = from;
    }
    /**
     * Getter method for property <tt>to</tt>.
     *
     * @return property value of to
     */
    public String getTo() {
        return to;
    }
    /**
     * Setter method for property <tt>to</tt>.
     *
     * @param to value to be assigned to property to
     */
    public void setTo(String to) {
        this.to = to;
    }
    /**
     * Getter method for property <tt>content</tt>.
     *
     * @return property value of content
     */
    public String getContent() {
        return content;
    }
    /**
     * Setter method for property <tt>content</tt>.
     *
     * @param content value to be assigned to property content
     */
    public void setContent(String content) {
        this.content = content;
    }
}

 

/**
 *
 * @author zhangwei_david
 * @version $Id: ProducerImpl.java, v 0.1 2015年1月31日 下午8:25:36 zhangwei_david Exp $
 */
@Component
public class ProducerImpl implements Producer {
    @Autowired
    private JmsTemplate jmsTemplate;
    /**
     */
    @Transactional
    public void send(Mail mail) {
        System.out.println("sende->" + mail);
        jmsTemplate.convertAndSend(mail);
    }
}

 

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:jms="http://www.springframework.org/schema/jms"
	xmlns:p="http://www.springframework.org/schema/p" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:aop="http://www.springframework.org/schema/aop" 
	xsi:schemaLocation="
		http://www.springframework.org/schema/beans
		http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
		http://www.springframework.org/shcema/jms
		http://www.springframework.org/schema/jms/spring-jms-3.0.xsd
		http://www.springframework.org/schema/context
		http://www.springframework.org/schema/context/spring-context-3.0.xsd
		http://www.springframework.org/schema/aop 
		http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
		">
	<aop:aspectj-autoproxy />
	<context:annotation-config />
	<context:component-scan base-package="com.cathy.demo.jms.*" />
	<!-- connectionFactory -->
	<bean id="connectionFactory" class="org.apache.activemq.ActiveMQConnectionFactory">
		<property name="brokerURL" value="tcp://localhost:61616"/>
	</bean>
	<!-- mailMessage converter -->
	<bean id="mailMessageConverter" class="com.cathy.demo.jms.convert.MailMessageConverter"/>
	<!-- jmsTemplate -->
	<bean id="jmsTemplate" class="org.springframework.jms.core.JmsTemplate">
		<property name="connectionFactory" ref="connectionFactory"/>
		<property name="defaultDestination" ref="topic"/>
		<property name="receiveTimeout" value="60000"/>
		<property name="pubSubDomain" value="true"/>
		<property name="sessionTransacted" value="true"/>   
		<property name="messageConverter" ref="mailMessageConverter"/>
	</bean>
	<!--
	<bean id="destination" class="org.apache.activemq.command.ActiveMQQueue">
		<constructor-arg value="message.queue"/>
	</bean>
	-->
	<!-- 主题 -->
	<bean id="topic" class="org.apache.activemq.command.ActiveMQTopic">
		<constructor-arg value="notifyTopic"/>
	</bean>
	<bean id="defaultMessageListener" class="com.cathy.demo.jms.listener.MailMessageListener">
		<property name="messageConverter" ref="mailMessageConverter"/>
	</bean>
	<!-- 消息接收监听器用于异步接收消息-->
    <bean class="org.springframework.jms.listener.DefaultMessageListenerContainer">  
        <property name="connectionFactory" ref="connectionFactory"/>  
        <property name="destination" ref="topic"/>
        <property name="sessionTransacted" value="true"/>
        <property name="messageListener" ref="defaultMessageListener"/>  
   </bean>
</beans>

 

/**
 *
 * @author zhangwei_david
 * @version $Id: Sender.java, v 0.1 2015年1月31日 下午8:47:18 zhangwei_david Exp $
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath*:META-INF/spring/jms-beans.xml")
public class SenderAndReciver {
    @Autowired
    private Producer producer;
    @Test
    public void testSend() {
        Mail mail = new Mail();
        mail.setMailId("testId");
        mail.setTo("david");
        mail.setFrom("cathy");
        mail.setContent("Hello");
        producer.send(mail);
    }
}

 测试的结果是:

log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
sende->Mail[mailId=testId,from=cathy,to=david,content=Hello]
on message:Mail[mailId=testId,from=cathy,to=david,content=Hello]

 

MessageListenerAdapter

 

消息监听器适配器代理消息的处理目标 通过反射监听方法,具有灵活的消息类型转换。允许监听器的方法来对邮件内容类型进行操作,完全独立于JMS API

 

定义一个消息处理目标方法

 

/**
 *
 * @author zhangwei_david
 * @version $Id: ListenerDelegate.java, v 0.1 2015年2月3日 下午2:32:11 zhangwei_david Exp $
 */
public class ListenerDelegate {
    public void handleMessage(@SuppressWarnings("rawtypes") Map map) {
        System.out.println("receive  MapMessage->" + map);
    }
}
 
<bean id="defaultListener" class="org.springframework.jms.listener.adapter.MessageListenerAdapter">
         <constructor-arg ref="listenerDelegate"/>
     </bean>
	<!-- 消息接收监听器用于异步接收消息-->
    <bean class="org.springframework.jms.listener.DefaultMessageListenerContainer">  
        <property name="connectionFactory" ref="connectionFactory"/>  
        <property name="destination" ref="topic"/>
        <property name="sessionAcknowledgeModeName" value="CLIENT_ACKNOWLEDGE"/>
        <property name="messageListener" ref="defaultListener"/> 
        <property name="sessionTransacted" value="true"/> 
   </bean>
 执行测试方法的结果是:

 

sende->Mail[mailId=testId,from=cathy,to=david,content=Hello]
on message:Mail[mailId=testId,from=cathy,to=david,content=Hello]
receive  MapMessage->{mailId=testId, from=cathy, to=david, content=Hello}
 那么在 MessageListenerAdapter中又是如何处理消息的呢?
public void onMessage(Message message, Session session) throws JMSException {
		// 获取代理方法
		Object delegate = getDelegate();
		// 如果代理方法不是当前类
		if (delegate != this) {
			// 如果代理方法是实现SessionAwareMessageListener接口的,直接将消息和session交给代理方法处理
			if (delegate instanceof SessionAwareMessageListener) {
				if (session != null) {
					((SessionAwareMessageListener) delegate).onMessage(message, session);
					return;
				}
				// session为null,且该代理对象未实现MessageListener接口则抛出一个异常
				else if (!(delegate instanceof MessageListener)) {
					throw new javax.jms.IllegalStateException("MessageListenerAdapter cannot handle a " +
							"SessionAwareMessageListener delegate if it hasn't been invoked with a Session itself");
				}
			}
			// 如果代理对象实现了MessageListener接口则将消息交给代理对象处理
			if (delegate instanceof MessageListener) {
				((MessageListener) delegate).onMessage(message);
				return;
			}
		}
		//将消息体转换为一个对象
		Object convertedMessage = extractMessage(message);
		// 获取这个消息的处理方法
		String methodName = getListenerMethodName(message, convertedMessage);
		if (methodName == null) {
			throw new javax.jms.IllegalStateException("No default listener method specified: " +
					"Either specify a non-null value for the 'defaultListenerMethod' property or " +
					"override the 'getListenerMethodName' method.");
		}
		// 反射调用处理方法处理消息
		Object[] listenerArguments = buildListenerArguments(convertedMessage);
		Object result = invokeListenerMethod(methodName, listenerArguments);
		if (result != null) {
			handleResult(result, message, session);
		}
		else {
			logger.trace("No result object given - no result to handle");
		}
	}
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