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ActiveMQ example source code file (SimpleQueueReceiver.java)

This example ActiveMQ source code file (SimpleQueueReceiver.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - ActiveMQ tags/keywords

api, jmsexception, jndi, jndi, logger, naming, namingexception, queue, queueconnectionfactory, queueconnectionfactory, queuesession, simplequeuereceiver, simplequeuereceiver, textmessage, textmessage

The ActiveMQ SimpleQueueReceiver.java source code

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * 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.
 */
package org.apache.activemq.demo;

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

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public final class SimpleQueueReceiver {

    private static final Logger LOG = LoggerFactory.getLogger(SimpleQueueReceiver.class);

    private SimpleQueueReceiver() {
    }

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

        /*
         * Read queue name from command line and display it.
         */
        if (args.length != 1) {
            LOG.info("Usage: java " + "SimpleQueueReceiver <queue-name>");
            System.exit(1);
        }
        queueName = args[0];
        LOG.info("Queue name is " + queueName);

        /*
         * Create a JNDI API InitialContext object if none exists yet.
         */
        try {
            jndiContext = new InitialContext();
        } catch (NamingException e) {
            LOG.info("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("QueueConnectionFactory");
            queue = (Queue)jndiContext.lookup(queueName);
        } catch (NamingException e) {
            LOG.info("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;
                        LOG.info("Reading message: " + message.getText());
                    } else {
                        break;
                    }
                }
            }
        } catch (JMSException e) {
            LOG.info("Exception occurred: " + e.toString());
        } finally {
            if (queueConnection != null) {
                try {
                    queueConnection.close();
                } catch (JMSException e) {
                }
            }
        }
    }
}

Other ActiveMQ examples (source code examples)

Here is a short list of links related to this ActiveMQ SimpleQueueReceiver.java source code file:

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