JMS样本

1、JMS它是一个制作AS提供Message服务。它接受由生成的消息(Message Provider)消息发出，并转发消息到消息消费者(Message  Consumer)。
2、JMS提供2的消息服务的类型：(1)Queue。这点，息消费者使用。(2)Topic。即公布和订阅。每一个消息能够转发给全部的订阅者(消费者)。
3、WEBLOGIC 8下的JMS配置：
(1)配置JMS Connection Factory
(2)配置JMS File Store(眼下所找到的文档都是配置File Store,事实上在详细的应用中。可能JMS JDBC Store更广泛，但临时没有找到资料)
(3)配置JMS Server
(4)在JMS Server的destinations中配置JMS Queue或者JMS Topic
当中提供给消息产生者和消息消费者使用的是JMS Connection Factory的JNDI和JMS Queue或者JMS Topic的JNDI。
4、消息产生者向JMS发送消息的步骤：
(1)使用JNDI查询对象JMS ConnectionFactory和Destination(JMS Queue/Topic)
(2)使用管理对象JMS ConnectionFactory建立连接Connection
(3)使用连接Connection 建立会话Session
(4)使用会话Session和管理对象Destination创建消息生产者MessageSender
(5)使用消息生产者MessageSender发送消息
一个消息发送者的样例：

package myjms; import java.util.*; import javax.naming.*; import javax.jms.*; public class MessageProducter { public static void main(String[] args) { String queueConnectionFactoryName = "myjmsconnectionfactory"; //JMS Connection Factory的JNDI String queueName = "myjmsqueue"; //JMS Queue或者JMS Topic的JNDI boolean transacted = false;//transaction模式 int acknowledgementMode = Session.AUTO_ACKNOWLEDGE;//acknowledgement模式 String message="Message need to send";//模拟须要发送的消息 Properties properties = new Properties(); properties.put(Context.INITIAL_CONTEXT_FACTORY,"weblogic.jndi.WLInitialContextFactory"); properties.put(Context.PROVIDER_URL, "t3://localhost:7001"); try { Context context = new InitialContext(properties); Object obj = context.lookup(queueConnectionFactoryName); QueueConnectionFactory queueConnectionFactory = (QueueConnectionFactory) obj;//JMS Connection Factory的获得 obj = context.lookup(queueName); Queue queue = (Queue) obj;//JMS Queue或者JMS Topic的获得 QueueConnection queueConnection=queueConnectionFactory.createQueueConnection();//产生连接 queueConnection.start(); QueueSession queueSession = queueConnection.createQueueSession(transacted, acknowledgementMode); TextMessage textMessage = queueSession.createTextMessage(); textMessage.clearBody(); textMessage.setText(message); QueueSender queueSender = queueSession.createSender(queue); queueSender.send(textMessage); if (transacted) { queueSession.commit(); } if (queueSender != null) { queueSender.close(); } if (queueSession != null) { queueSession.close(); } if (queueConnection != null) { queueConnection.close(); } } catch(Exception ex){ ex.printStackTrace(); } } }

5、消息消费者从JMS接受消息的步骤：
(1)使用JNDI查询对象JMS ConnectionFactory和Destination(JMS Queue/Topic)
(2)使用管理对象JMS ConnectionFactory建立连接Connection
(3)使用连接Connection 建立会话Session
(4)使用会话Session和管理对象Destination创建消息消费者MessageReceiver
(5)使用消息消费者MessageReceiver接受消息，须要用setMessageListener将MessageListener接口绑定到MessageReceiver
消息消费者必须实现了MessageListener接口，须要定义onMessage事件方法。

一个消息消费者的样例：

package myjms; import java.util.*; import javax.naming.*; import javax.jms.*; public class MessageReciever implements MessageListener { public void onMessage(Message message) { if (message instanceof TextMessage) { TextMessage textMessage = (TextMessage) message; try { System.out.println("Message content is:" + textMessage.getText()); } catch (JMSException e) { e.printStackTrace(); } } } public static void main(String[] args) { MessageReciever msgRcvr=new MessageReciever(); String queueConnectionFactoryName = "myjmsconnectionfactory"; String queueName = "myjmsqueue"; boolean transacted = false; int acknowledgementMode = Session.AUTO_ACKNOWLEDGE; Properties properties = new Properties(); properties.put(Context.INITIAL_CONTEXT_FACTORY, "weblogic.jndi.WLInitialContextFactory"); properties.put(Context.PROVIDER_URL, "t3://localhost:7001"); try { Context context = new InitialContext(properties); Object obj = context.lookup(queueConnectionFactoryName); QueueConnectionFactory queueConnectionFactory = (QueueConnectionFactory) obj; obj = context.lookup(queueName); Queue queue = (Queue) obj; QueueConnection queueConnection = queueConnectionFactory. createQueueConnection(); queueConnection.start(); QueueSession queueSession = queueConnection.createQueueSession(transacted, acknowledgementMode); QueueReceiver queueReceiver = queueSession.createReceiver(queue); queueReceiver.setMessageListener(msgRcvr); synchronized(msgRcvr){ msgRcvr.wait(100000); } if (queueReceiver != null) { queueReceiver.close(); } if (queueSession != null) { queueSession.close(); } if (queueConnection != null) { queueConnection.close(); } } catch (Exception ex) { ex.printStackTrace(); } } }

6、Message-driven Bean
MDB它实际上是一个消息消费者client计划。它由AS EJB Container要管理。在JBUILDER产生MDB很easy。