深入掌握JMS（十二）：MDB

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        在EJB3中，一个MDB(消息驱动Bean)就是一个实现了MessageListener接口的POJO，下面就是一个简单的MDB。 

@MessageDriven(activationConfig={@ActivationConfigProperty(propertyName="destinationType", propertyValue="javax.jms.Queue"), @ActivationConfigProperty(propertyName="destination", propertyValue="queue/testQueue")}) 
public class SimpleMDB implements MessageListener { 
    public void onMessage(Message message) { 
        try { 
            System.out.println("Receive Message : " + ((TextMessage)message).getText()); 
        } catch (JMSException e) { 
            e.printStackTrace(); 
        } 
    } 
}

        它要求必须标注为@MessageDriven，它所监听Destination通过标注属性来注入。

        下面是一个发送消息的StatelessBean：

@Remote 
public interface IMessageSender { 
    public void sendMessage(String content) throws Exception; 
}

@Stateless 
@Remote 
public class MessageSender implements IMessageSender {

    @Resource(mappedName="ConnectionFactory") 
    private ConnectionFactory factory; 

    @Resource(mappedName="queue/testQueue") 
    private Queue queue; 

    public void sendMessage(String content) throws Exception { 
        Connection cn = factory.createConnection(); 
        Session session = cn.createSession(false, Session.AUTO_ACKNOWLEDGE); 
        MessageProducer producer = session.createProducer(queue); 
        producer.send(session.createTextMessage(content)); 
    } 
}

        这个EJB只有一个方法SendMessage，ConnectionFactory和Queue通过标注注入。

        接下来是客户端： 

public class MessageSenderClient { 
    public static void main(String[] args) throws Exception { 
        Properties props = new Properties(); 
        props.setProperty(Context.INITIAL_CONTEXT_FACTORY, "org.jnp.interfaces.NamingContextFactory"); 
        props.setProperty(Context.PROVIDER_URL, "localhost:2099"); 
        Context context = new InitialContext(props); 
        IMessageSender messageSender = (IMessageSender) context.lookup("MessageSender/remote"); 
        messageSender.sendMessage("Hello"); 
    } 
} 

        它通过JNDI查找到上面的EJB，然后调用sengMessage。

 

文章来源：http://www.cnblogs.com/guthing/archive/2010/06/12/1757189.html