简单EJB3消息驱动Bean
Jms规范里的两种message传输方式Topic和Queue,两者的对比如下表():
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TopicQueue概要Publish Subscribe messaging 发布订阅消息Point-to-Point 点对点有无状态topic数据默认不落地,是无状态的。Queue数据默认会在mq服务器上以文件形式保存,比如Active MQ一般保存在$AMQ_HOME\data\kr-store\data下面。也可以配置成DB存储。
完整性保障并不保证publisher发布的每条数据,Subscriber都能接受到。Queue保证每条数据都能被receiver接收。消息是否会丢失一般来说publisher发布消息到某一个topic时,只有正在监听该topic地址的sub能够接收到消息;如果没有sub在监听,该topic就丢失了。Sender发送消息到目标Queue,receiver可以异步接收这个Queue上的消息。Queue上的消息如果暂时没有receiver来取,也不会丢失。消息发布接收策略一对多的消息发布接收策略,监听同一个topic地址的多个sub都能收到publisher发送的消息。Sub接收完通知mq服务器一对一的消息发布接收策略,一个sender发送的消息,只能有一个receiver接收。receiver接收完后,通知mq服务器已接收,mq服务器对queue里的消息采取删除或其他操作。?
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Queue
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发布Queue 部署在jboss 目录 使用是默认的server? jboss-4.2.3.GA\server\default\deploy
文件名称必需是?? 文件名-service.xml 格式
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<?xml version="1.0" encoding="UTF-8"?><server><mbean code="org.jboss.mq.server.jmx.Queue"name="jboss.mq.destination:service=Queue,name=leamQueue"><attribute name="JNDIName">queue/leamQueue</attribute><depends optional-attribute-name="DestinationManager">jboss.mq:service=DestinationManager</depends></mbean></server>
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发布成功之后可以在jboss web控制页面? /jmx-console/HtmlAdaptor查看已经发布的名称
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+- queue (class: org.jnp.interfaces.NamingContext) | +- A (class: org.jboss.mq.SpyQueue) | +- testQueue (class: org.jboss.mq.SpyQueue) | +- ex (class: org.jboss.mq.SpyQueue) | +- leamQueue (class: org.jboss.mq.SpyQueue)
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新建类 发送Queue消息
/** * @param args */public static void main(String[] args) {// TODO Auto-generated method stubtry {InitialContext ctx=new InitialContext();QueueConnectionFactory factory= (QueueConnectionFactory)ctx.lookup("QueueConnectionFactory");QueueConnection conn=factory.createQueueConnection();QueueSession session= conn.createQueueSession(false, QueueSession.AUTO_ACKNOWLEDGE);Destination destination=(Destination)ctx.lookup("queue/leamQueue");MessageProducer prd=session.createProducer(destination);prd.send(session.createTextMessage("你好 leam 我是queue消息"));session.close();conn.close();System.out.println("发送完成");} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}?
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获取发送的Queue消息 配置获取jndi文件 必需要和获取消息类同一个包下
jndi.properties 文件内容
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java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory
java.naming.provider.url=localhost:1099
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新建类获取 Queue消息
@MessageDriven(activationConfig = {@ActivationConfigProperty(propertyName = "destinationType", propertyValue = "javax.jms.Queue"),@ActivationConfigProperty(propertyName = "destination", propertyValue = "queue/leamQueue") })public class MessageDriverBean implements MessageListener {public void onMessage(Message message) {TextMessage txtmsg=(TextMessage)message;try {System.out.print(txtmsg.getText());} catch (JMSException e) {e.printStackTrace();}}}?
所有代码写完之后 打包jar发布到jboss? 输出
你好 leam 我是queue消息?
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发布Topic部署在jboss 目录 使用是默认的server? jboss-4.2.3.GA\server\default\deploy
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<?xml version="1.0" encoding="UTF-8"?><server><mbean code="org.jboss.mq.server.jmx.Topic"name="jboss.mq.destination:service=Topic,name=leamTopic"><attribute name="JNDIName">topic/leamTopic</attribute><dependsoptional-attribute-name="DestinationManager">jboss.mq:service=DestinationManager</depends></mbean></server>
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发布成功之后可以在jboss web控制页面? /jmx-console/HtmlAdaptor查看已经发布的名称
+- topic (class: org.jnp.interfaces.NamingContext) | +- testDurableTopic (class: org.jboss.mq.SpyTopic) | +- testTopic (class: org.jboss.mq.SpyTopic) | +- securedTopic (class: org.jboss.mq.SpyTopic) | +- leamTopic (class: org.jboss.mq.SpyTopic)
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新建类 发送Topic消息
public class TopicSender {/** * @param args */public static void main(String[] args) {try {InitialContext ctx=new InitialContext();TopicConnectionFactory factory= (TopicConnectionFactory)ctx.lookup("TopicConnectionFactory");TopicConnection conn=factory.createTopicConnection();TopicSession session= conn.createTopicSession(false, TopicSession.AUTO_ACKNOWLEDGE);Destination destination=(Destination)ctx.lookup("topic/leamTopic");MessageProducer prd=session.createProducer(destination);prd.send(session.createTextMessage("你好 leam 我是topic消息"));session.close();conn.close();System.out.println("发送完成");} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}}
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新建类获取 Topic消息
@MessageDriven(activationConfig = {@ActivationConfigProperty(propertyName = "destinationType", propertyValue = "javax.jms.Topic"),@ActivationConfigProperty(propertyName = "destination",?propertyValue = "topic/leamTopic") })public class ReceiveBean implements MessageListener {public void onMessage(Message message) {TextMessage txtmsg=(TextMessage)message;try {System.out.print(this.getClass()+txtmsg.getText());} catch (JMSException e) {e.printStackTrace();}}}