content: /**
   * 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.advisory;
  
  import java.util.Set;
  import java.util.concurrent.CopyOnWriteArraySet;
  import java.util.concurrent.atomic.AtomicBoolean;
  
  import jakarta.jms.Connection;
  import jakarta.jms.JMSException;
  import jakarta.jms.Message;
  import jakarta.jms.MessageConsumer;
  import jakarta.jms.MessageListener;
  import jakarta.jms.Session;
  
  import org.apache.activemq.command.ActiveMQDestination;
  import org.apache.activemq.command.ActiveMQMessage;
  import org.apache.activemq.command.ActiveMQQueue;
  import org.apache.activemq.command.ActiveMQTempQueue;
  import org.apache.activemq.command.ActiveMQTempTopic;
  import org.apache.activemq.command.ActiveMQTopic;
  import org.apache.activemq.command.DestinationInfo;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * A helper class which keeps track of the Destinations available in a broker and allows you to listen to them
   * being created or deleted.
   *
   * 
   */
  public class DestinationSource implements MessageListener {
      private static final Logger LOG = LoggerFactory.getLogger(ConsumerEventSource.class);
      private AtomicBoolean started = new AtomicBoolean(false);
      private final Connection connection;
      private Session session;
      private MessageConsumer queueConsumer;
      private MessageConsumer topicConsumer;
      private MessageConsumer tempTopicConsumer;
      private MessageConsumer tempQueueConsumer;
      private Set<ActiveMQQueue> queues = new CopyOnWriteArraySet<ActiveMQQueue>();
      private Set<ActiveMQTopic> topics = new CopyOnWriteArraySet<ActiveMQTopic>();
      private Set<ActiveMQTempQueue> temporaryQueues = new CopyOnWriteArraySet<ActiveMQTempQueue>();
      private Set<ActiveMQTempTopic> temporaryTopics = new CopyOnWriteArraySet<ActiveMQTempTopic>();
      private DestinationListener listener;
  
      public DestinationSource(Connection connection) throws JMSException {
          this.connection = connection;
      }
  
      public DestinationListener getListener() {
          return listener;
      }
  
      public void setDestinationListener(DestinationListener listener) {
          this.listener = listener;
      }
  
      /**
       * Returns the current queues available on the broker
       */
      public Set<ActiveMQQueue> getQueues() {
          return queues;
      }
  
      /**
       * Returns the current topics on the broker
       */
      public Set<ActiveMQTopic> getTopics() {
          return topics;
      }
  
      /**
       * Returns the current temporary topics available on the broker
       */
      public Set<ActiveMQTempQueue> getTemporaryQueues() {
          return temporaryQueues;
      }
  
      /**
       * Returns the current temporary queues available on the broker
       */
      public Set<ActiveMQTempTopic> getTemporaryTopics() {
          return temporaryTopics;
      }
  
      public void start() throws JMSException {
          if (started.compareAndSet(false, true)) {
              session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
              queueConsumer = session.createConsumer(AdvisorySupport.QUEUE_ADVISORY_TOPIC);
              queueConsumer.setMessageListener(this);
  
              topicConsumer = session.createConsumer(AdvisorySupport.TOPIC_ADVISORY_TOPIC);
              topicConsumer.setMessageListener(this);
  
              tempQueueConsumer = session.createConsumer(AdvisorySupport.TEMP_QUEUE_ADVISORY_TOPIC);
              tempQueueConsumer.setMessageListener(this);
  
              tempTopicConsumer = session.createConsumer(AdvisorySupport.TEMP_TOPIC_ADVISORY_TOPIC);
              tempTopicConsumer.setMessageListener(this);
          }
      }
  
      public void stop() throws JMSException {
          if (started.compareAndSet(true, false)) {
              if (session != null) {
                  session.close();
              }
          }
      }
  
      public void onMessage(Message message) {
          if (message instanceof ActiveMQMessage) {
              ActiveMQMessage activeMessage = (ActiveMQMessage) message;
              Object command = activeMessage.getDataStructure();
              if (command instanceof DestinationInfo) {
                  DestinationInfo destinationInfo = (DestinationInfo) command;
                  DestinationEvent event = new DestinationEvent(this, destinationInfo);
                  fireDestinationEvent(event);
              }
              else {
                  LOG.warn("Unknown dataStructure: " + command);
              }
          }
          else {
              LOG.warn("Unknown message type: " + message + ". Message ignored");
          }
      }
  
      protected void fireDestinationEvent(DestinationEvent event) {
          // now lets update the data structures
          ActiveMQDestination destination = event.getDestination();
          boolean add = event.isAddOperation();
          if (destination instanceof ActiveMQQueue) {
              ActiveMQQueue queue = (ActiveMQQueue) destination;
              if (add) {
                  queues.add(queue);
              }
              else {
                  queues.remove(queue);
              }
          }
          else if (destination instanceof ActiveMQTopic) {
              ActiveMQTopic topic = (ActiveMQTopic) destination;
              if (add) {
                  topics.add(topic);
              }
              else {
                  topics.remove(topic);
              }
          }
          else if (destination instanceof ActiveMQTempQueue) {
              ActiveMQTempQueue queue = (ActiveMQTempQueue) destination;
              if (add) {
                  temporaryQueues.add(queue);
              }
              else {
                  temporaryQueues.remove(queue);
              }
          }
          else if (destination instanceof ActiveMQTempTopic) {
              ActiveMQTempTopic topic = (ActiveMQTempTopic) destination;
              if (add) {
                  temporaryTopics.add(topic);
              }
              else {
                  temporaryTopics.remove(topic);
              }
          }
          else {
              LOG.warn("Unknown destination type: " + destination);
          }
          if (listener != null) {
              listener.onDestinationEvent(event);
          }
      }
  }
  