/**
 * The SimpleQueueReceiver class consists only of a main method,
 * which fetches one or more messages from a queue using
 * synchronous message delivery.  Run this program in conjunction
 * with SimpleQueueSender.  Specify a queue name on the command
 * line when you run the program.
 */
import javax.jms.*;
import javax.naming.*;

public class SimpleQueueReceiver {

    /**
     * Main method.
     *
     * @param args     the queue used by the example
     */
    public static void main(String[] args) {
        String                  queueName = "wwseMatchedOrderQueue";
        Context                 jndiContext = null;
        QueueConnectionFactory  queueConnectionFactory = null;
        QueueConnection         queueConnection = null;
        QueueSession            queueSession = null;
        Queue                   queue = null;
        QueueReceiver           queueReceiver = null;
        TextMessage             message = null;

        /*
         * Create a JNDI API InitialContext object if none exists
         * yet.
         */
        try {
            jndiContext = new InitialContext();
        } catch (NamingException e) {
            System.out.println("Could not create JNDI API " +
                "context: " + e.toString());
            System.exit(1);
        }

        /*
         * Look up connection factory and queue.  If either does
         * not exist, exit.
         */
        try {
            queueConnectionFactory = (QueueConnectionFactory)
                jndiContext.lookup("wwseConnFactory");
            queue = (Queue) jndiContext.lookup(queueName);
        } catch (NamingException e) {
            System.out.println("JNDI API lookup failed: " +
                e.toString());
            System.exit(1);
        }

        /*
         * Create connection.
         * Create session from connection; false means session is
         * not transacted.
         * Create receiver, then start message delivery.
         * Receive all text messages from queue until
         * a non-text message is received indicating end of
         * message stream.
         * Close connection.
         */
        try {
            queueConnection =
                queueConnectionFactory.createQueueConnection();
            queueSession =
                queueConnection.createQueueSession(false,
                    Session.AUTO_ACKNOWLEDGE);
            queueReceiver = queueSession.createReceiver(queue);
            queueConnection.start();
            while (true) {
                Message m = queueReceiver.receive(1);
                if (m != null) {
                    if (m instanceof TextMessage) {
                        message = (TextMessage) m;
                        System.out.println("Reading message: " +
                            message.getText());
                    } else {
                        break;
                    }
                }
            }
        } catch (JMSException e) {
            System.out.println("Exception occurred: " +
                e.toString());
        } finally {
            if (queueConnection != null) {
                try {
                    queueConnection.close();
                } catch (JMSException e) {}
            }
        }
    }
}