/**
 * 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 SimpleQueueSender class consists only of a main method,
 * which sends several messages to a queue.
 *
 * Run this program in conjunction with SimpleQueueReceiver.
 * Specify a queue name on the command line when you run the
 * program.  By default, the program sends one message.  Specify
 * a number after the queue name to send that number of messages.
 */
package org.apache.activemq.demo;

// START SNIPPET: demo

import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.MessageProducer;
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;

/**
 * A simple polymorphic JMS producer which can work with Queues or Topics which
 * uses JNDI to lookup the JMS connection factory and destination
 */
public final class SimpleProducer {

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

   private SimpleProducer() {
   }

   /**
    * @param args the destination name to send to and optionally, the number of
    *             messages to send
    */
   public static void main(String[] args) {
      Context jndiContext = null;
      ConnectionFactory connectionFactory = null;
      Connection connection = null;
      Session session = null;
      Destination destination = null;
      MessageProducer producer = null;
      String destinationName = null;
      final int numMsgs;

      if ((args.length < 1) || (args.length > 2)) {
         LOG.info("Usage: java SimpleProducer <destination-name> [<number-of-messages>]");
         System.exit(1);
      }
      destinationName = args[0];
      LOG.info("Destination name is " + destinationName);
      if (args.length == 2) {
         numMsgs = (new Integer(args[1])).intValue();
      }
      else {
         numMsgs = 1;
      }

        /*
         * Create a JNDI API InitialContext object
         */
      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 destination.
         */
      try {
         connectionFactory = (ConnectionFactory) jndiContext.lookup("ConnectionFactory");
         destination = (Destination) jndiContext.lookup(destinationName);
      }
      catch (NamingException e) {
         LOG.info("JNDI API lookup failed: " + e);
         System.exit(1);
      }

        /*
         * Create connection. Create session from connection; false means
         * session is not transacted. Create sender and text message. Send
         * messages, varying text slightly. Send end-of-messages message.
         * Finally, close connection.
         */
      try {
         connection = connectionFactory.createConnection();
         session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
         producer = session.createProducer(destination);
         TextMessage message = session.createTextMessage();
         for (int i = 0; i < numMsgs; i++) {
            message.setText("This is message " + (i + 1));
            LOG.info("Sending message: " + message.getText());
            producer.send(message);
         }

            /*
             * Send a non-text control message indicating end of messages.
             */
         producer.send(session.createMessage());
      }
      catch (JMSException e) {
         LOG.info("Exception occurred: " + e);
      }
      finally {
         if (connection != null) {
            try {
               connection.close();
            }
            catch (JMSException e) {
            }
         }
      }
   }
}

// END SNIPPET: demo
