| /* |
| * 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. |
| */ |
| package org.apache.activemq.artemis.jms.example; |
| |
| import javax.jms.Connection; |
| import javax.jms.ConnectionFactory; |
| import javax.jms.Message; |
| import javax.jms.MessageConsumer; |
| import javax.jms.MessageProducer; |
| import javax.jms.Queue; |
| import javax.jms.QueueConnection; |
| import javax.jms.QueueRequestor; |
| import javax.jms.QueueSession; |
| import javax.jms.Session; |
| import javax.jms.TextMessage; |
| |
| import org.apache.activemq.artemis.api.jms.ActiveMQJMSClient; |
| import org.apache.activemq.artemis.api.jms.ActiveMQJMSConstants; |
| import org.apache.activemq.artemis.api.jms.management.JMSManagementHelper; |
| import org.apache.activemq.artemis.api.core.management.ResourceNames; |
| import org.apache.activemq.artemis.jms.client.ActiveMQConnectionFactory; |
| |
| /** |
| * This example demonstrates the use of ActiveMQ Artemis "pre-acknowledge" functionality where |
| * messages are acknowledged before they are delivered to the consumer. |
| * |
| * Please see the readme for more details. |
| */ |
| public class PreacknowledgeExample { |
| |
| public static void main(final String[] args) throws Exception { |
| Connection connection = null; |
| try { |
| |
| // Step 2. instantiate the queue object |
| Queue queue = ActiveMQJMSClient.createQueue("exampleQueue"); |
| |
| // new connection factory |
| ConnectionFactory cf = new ActiveMQConnectionFactory(); |
| |
| // Step 3. Create a the JMS objects |
| connection = cf.createConnection(); |
| |
| Session session = connection.createSession(false, ActiveMQJMSConstants.PRE_ACKNOWLEDGE); |
| |
| MessageProducer producer = session.createProducer(queue); |
| |
| MessageConsumer messageConsumer = session.createConsumer(queue); |
| |
| // Step 4. Create and send a message |
| TextMessage message1 = session.createTextMessage("This is a text message 1"); |
| |
| producer.send(message1); |
| |
| System.out.println("Sent message: " + message1.getText()); |
| |
| // Step 5. Print out the message count of the queue. The queue contains one message as expected |
| // delivery has not yet started on the queue |
| int count = getMessageCount(connection); |
| |
| System.out.println("Queue message count is " + count); |
| |
| // Step 6. Start the Connection, delivery will now start. Give a little time for delivery to occur. |
| connection.start(); |
| |
| Thread.sleep(1000); |
| |
| // Step 7. Print out the message countof the queue. It should now be zero, since the message has |
| // already been acknowledged even before the consumer has received it. |
| count = getMessageCount(connection); |
| |
| System.out.println("Queue message count is now " + count); |
| |
| if (count != 0) { |
| throw new IllegalStateException("Queue message count is not 0."); |
| } |
| |
| // Step 8. Finally, receive the message |
| TextMessage messageReceived = (TextMessage) messageConsumer.receive(5000); |
| |
| System.out.println("Received message: " + messageReceived.getText()); |
| } finally { |
| // Step 9. Be sure to close our resources! |
| if (connection != null) { |
| connection.close(); |
| } |
| } |
| } |
| |
| // To do this we send a management message to get the message count. |
| // In real life you wouldn't create a new session every time you send a management message |
| private static int getMessageCount(final Connection connection) throws Exception { |
| QueueSession session = ((QueueConnection) connection).createQueueSession(false, Session.AUTO_ACKNOWLEDGE); |
| |
| Queue managementQueue = ActiveMQJMSClient.createQueue("activemq.management"); |
| |
| QueueRequestor requestor = new QueueRequestor(session, managementQueue); |
| |
| connection.start(); |
| |
| Message m = session.createMessage(); |
| |
| JMSManagementHelper.putAttribute(m, ResourceNames.QUEUE + "exampleQueue", "messageCount"); |
| |
| Message response = requestor.request(m); |
| |
| int messageCount = (Integer) JMSManagementHelper.getResult(response, Integer.class); |
| |
| return messageCount; |
| } |
| |
| } |