使用Spring JMS简化异步消息处理

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http://www.onjava.com/lpt/a/6490

这片文章介绍了Spring是如何简化异步消息调用的，它通过一个贷款的例子来说Spring是如何减少

开发中的量的。

下面是传统开发需要的代码量

public void sendMessage() {    queueName = "queue/CreditRequestSendQueue";    System.out.println("Queue name is " + queueName);    /*     * Create JNDI Initial Context     */    try {        Hashtable env = new Hashtable();        env.put("java.naming.factory.initial",            "org.jnp.interfaces.NamingContextFactory");        env.put("java.naming.provider.url","localhost");        env.put("java.naming.factory.url.pkgs",            "org.jnp.interfaces:org.jboss.naming");        jndiContext = new InitialContext(env);    } catch (NamingException e) {        System.out.println("Could not create JNDI API " +            "context: " + e.toString());    }    /*     * Get queue connection factory and queue objects from JNDI context.     */    try {        queueConnectionFactory = (QueueConnectionFactory)        jndiContext.lookup("UIL2ConnectionFactory");        queue = (Queue) jndiContext.lookup(queueName);    } catch (NamingException e) {        System.out.println("JNDI API lookup failed: " +            e.toString());    }    /*     * Create connection, session, sender objects.     * Send the message.     * Cleanup JMS connection.     */    try {        queueConnection =            queueConnectionFactory.createQueueConnection();        queueSession = queueConnection.createQueueSession(false,                Session.AUTO_ACKNOWLEDGE);        queueSender = queueSession.createSender(queue);        message = queueSession.createTextMessage();        message.setText("This is a sample JMS message.");        System.out.println("Sending message: " + message.getText());        queueSender.send(message);    } catch (JMSException e) {        System.out.println("Exception occurred: " + e.toString());    } finally {        if (queueConnection != null) {            try {                queueConnection.close();            } catch (JMSException e) {}        }    }}

然后是Spring的代码

public void send() {    try {        ClassPathXmlApplicationContext appContext = new

ClassPathXmlApplicationContext(new String[] {                "spring-jms.xml"});        System.out.println("Classpath loaded");        JMSSender jmsSender = (JMSSender)appContext.getBean("jmsSender");        jmsSender.sendMesage();        System.out.println("Message sent using Spring JMS.");    } catch(Exception e) {        e.printStackTrace();    }}

表面上看Spring获胜，代码少了很多，但是我们再来看看Spring配置的XML

                                        org.jnp.interfaces.NamingContextFactory                                        localhost                                        org.jnp.interfaces:org.jboss.naming                        
                            UIL2ConnectionFactory    
                            queue/CreditRequestSendQueue    
                            queue/CreditReqeustReceiveQueue    
                                            30000    
                
                
 
我们开始认清Spring的真面目把。无厘头的配置，XML的梦魇。从一种混乱到另一种还乱。