Java tutorial
/**************************************************************** * Licensed to the AOS Community (AOS) under one or more * * contributor license agreements. See the NOTICE file * * distributed with this work for additional information * * regarding copyright ownership. The AOS 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 io.datalayer.activemq.producer; // START SNIPPET: demo import javax.jms.JMSException; import javax.jms.Queue; import javax.jms.QueueConnection; import javax.jms.QueueConnectionFactory; import javax.jms.QueueSender; 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.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; public final class SimpleQueueSender { private static final Log LOG = LogFactory.getLog(SimpleQueueSender.class); private SimpleQueueSender() { } /** * Main method. * * @param args the queue used by the example and, optionally, the number of * messages to send */ public static void main(String... args) { String queueName = null; Context jndiContext = null; QueueConnectionFactory queueConnectionFactory = null; QueueConnection queueConnection = null; QueueSession queueSession = null; Queue queue = null; QueueSender queueSender = null; TextMessage message = null; final int numMsgs; if ((args.length < 1) || (args.length > 2)) { LOG.info("Usage: java SimpleQueueSender " + "<queue-name> [<number-of-messages>]"); System.exit(1); } queueName = args[0]; LOG.info("Queue name is " + queueName); if (args.length == 2) { numMsgs = (new Integer(args[1])).intValue(); } else { numMsgs = 1; } /* * 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); 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 { queueConnection = queueConnectionFactory.createQueueConnection(); queueSession = queueConnection.createQueueSession(false, Session.AUTO_ACKNOWLEDGE); queueSender = queueSession.createSender(queue); message = queueSession.createTextMessage(); for (int i = 0; i < numMsgs; i++) { message.setText("This is message " + (i + 1)); LOG.info("Sending message: " + message.getText()); queueSender.send(message); } /* * Send a non-text control message indicating end of messages. */ queueSender.send(queueSession.createMessage()); } catch (JMSException e) { LOG.info("Exception occurred: " + e.toString()); } finally { if (queueConnection != null) { try { queueConnection.close(); } catch (JMSException e) { } } } } } // END SNIPPET: demo