QueueRequestor Example

The following code shows how to use the QueueRequestor.

The QueueRequestor is actually quite lame. Internally it does

QueueRecevier.receive()

which will wait forever if there is nobody listening to your requests. Better would to use a timeout,

QueueRecevier.recieve(timeout);

  Code

import java.util.Properties;

import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.Queue;
import javax.jms.QueueConnection;
import javax.jms.QueueConnectionFactory;
import javax.jms.QueueReceiver;
import javax.jms.QueueRequestor;
import javax.jms.QueueSender;
import javax.jms.QueueSession;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.naming.Context;
import javax.naming.InitialContext;

public class Client implements MessageListener
{
   public static void main(String[] args) throws Exception
   {
      log.info("Creating jndi context - alternatively use a jndi.properties");
      Properties properties = new Properties();
      properties.put(Context.INITIAL_CONTEXT_FACTORY, "org.jnp.interfaces.NamingContextFactory");
      properties.put(Context.URL_PKG_PREFIXES, "org.jnp.interfaces");
      properties.put(Context.PROVIDER_URL, "localhost");
      InitialContext ctx = new InitialContext(properties);

      log.info("Looking up queue");
      Queue queue = (Queue) ctx.lookup("queue/testQueue");

      log.info("Looking up connection factory");
      QueueConnectionFactory qcf = (QueueConnectionFactory) ctx.lookup("UIL2ConnectionFactory");

      log.info("Creating connection");
      QueueConnection qc = qcf.createQueueConnection();
      try
      {
         log.info("Creating session");
         QueueSession qs = qc.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);

         log.info("Creating receiver");
         QueueReceiver receiver = qs.createReceiver(queue);

         log.info("Set the message listener");
         receiver.setMessageListener(new Client(qs));

         log.info("You have to start the connection before receiving messages");
         qc.start();

         log.info("Creating queue requestor session");
         QueueSession qrs = qc.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);
         
         log.info("Creating queue requestor");
         QueueRequestor qr = new QueueRequestor(qrs, queue);

         log.info("Creating message");
         TextMessage hello = qs.createTextMessage("hello");

         log.info("Sending request");
         Message response = qr.request(hello);

         log.info("Close the queue requestor");
         qr.close();

         log.info("Got response " + response);
      }
      finally
      {
         qc.close();
      }
   }

   QueueSession session;

   public Client(QueueSession session)
   {
      this.session = session;
   }

   public void onMessage(Message message)
   {
      log.info("Processing message: " + message);
      try
      {
         Queue replyQueue = (Queue) message.getJMSReplyTo();
         log.info("Reply queue is: " + replyQueue);

         log.info("Creating sender");
         QueueSender sender = session.createSender(replyQueue);

         log.info("Creating reply");
         TextMessage reply = session.createTextMessage("Reply");

         log.info("Sending reply");
         sender.send(reply);

         log.info("Tidyup sender - you could be processing many requests");
         sender.close();
      }
      catch (JMSException e)
      {
         log.error("Got unexpected error", e);
         System.exit(0);
      }
   }

   public static class log
   {
      public static void info(String message)
      {
         System.out.println(message);
      }

      public static void error(String message, Throwable t)
      {
         System.err.println(message);
         t.printStackTrace();
      }
   }
}

Instructions

To compile it:
javac -classpath JBOSS_HOME/client/jbossall-client.jar Client.java
or windows
javac -classpath JBOSS_HOME\client\jbossall-client.jar Client.java

To run it:
java -classpath .:JBOSS_HOME/client/jbossall-client.jar Client
or windows
java -classpath .;JBOSS_HOME\client\jbossall-client.jar Client

Output

 
Creating jndi context - alternatively use a jndi.properties
Looking up queue
Looking up connection factory
Creating connection
Creating session
Creating receiver
Set the message listener
You have to start the connection before receiving messages
Creating queue requestor session
Creating queue requestor
Creating message
Sending request
Processing message: SpyTextMessage {
Header { 
    jmsDestination  : QUEUE.testQueue
    jmsDeliveryMode : 2
    jmsExpiration   : 0
    jmsPriority     : 4
    jmsMessageID    : ID:1-10825512815071
    jmsTimeStamp    : 1082551281507
    jmsCorrelationID: null
    jmsReplyTo      : QUEUE.JMS_TQ1
    jmsType         : null
    jmsRedelivered  : false
    jmsProperties   : {}
    jmsPropReadWrite: false
    msgReadOnly     : true
    producerClientId: ID:1
}
Body {
    text            :hello
}
}
Reply queue is: QUEUE.JMS_TQ1
Creating sender
Creating reply
Sending reply
Tidyup sender - you could be processing many requests
Close the queue requestor
Got response SpyTextMessage {
Header { 
   jmsDestination  : QUEUE.JMS_TQ1
   jmsDeliveryMode : 1
   jmsExpiration   : 0
   jmsPriority     : 4
   jmsMessageID    : ID:1-10825512820892
   jmsTimeStamp    : 1082551282089
   jmsCorrelationID: null
   jmsReplyTo      : null
   jmsType         : null
   jmsRedelivered  : false
   jmsProperties   : {}
   jmsPropReadWrite: false
   msgReadOnly     : true
   producerClientId: ID:1
}
Body {
   text            :Reply
}
}