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ActiveMQ example source code file (CamelEndpointLoader.java)

This example ActiveMQ source code file (CamelEndpointLoader.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

activemqcomponent, activemqconfiguration, activemqqueue, activemqqueue, activemqtopic, annotation, camelendpointloader, connection, endpoint, enhancedconnection, enhancedconnection, exception, exception, string, string, util

The ActiveMQ CamelEndpointLoader.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.
 */
package org.apache.activemq.camel.component;

import java.util.Set;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.jms.Connection;
import javax.jms.ConnectionFactory;

import org.apache.activemq.EnhancedConnection;
import org.apache.activemq.advisory.DestinationEvent;
import org.apache.activemq.advisory.DestinationListener;
import org.apache.activemq.advisory.DestinationSource;
import org.apache.activemq.command.ActiveMQDestination;
import org.apache.activemq.command.ActiveMQQueue;
import org.apache.activemq.command.ActiveMQTopic;
import org.apache.camel.CamelContext;
import org.apache.camel.CamelContextAware;
import org.apache.camel.Endpoint;
import org.apache.camel.component.jms.JmsEndpoint;
import org.apache.camel.component.jms.JmsQueueEndpoint;
import org.apache.camel.util.ObjectHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * A helper bean which populates a {@link CamelContext} with ActiveMQ Queue endpoints
 *
 *
 * @org.apache.xbean.XBean
 */
public class CamelEndpointLoader implements CamelContextAware {
    private static final transient Logger LOG = LoggerFactory.getLogger(CamelEndpointLoader.class);
    private CamelContext camelContext;
    private EnhancedConnection connection;
    private ConnectionFactory connectionFactory;
    private ActiveMQComponent component;

    public CamelEndpointLoader() {
    }

    public CamelEndpointLoader(CamelContext camelContext) {
        this.camelContext = camelContext;
    }

    /**
     *
     * @throws Exception
     * @org.apache.xbean.InitMethod
     */
    @PostConstruct
    public void afterPropertiesSet() throws Exception {
        ObjectHelper.notNull(camelContext, "camelContext");
        if (connection == null) {
            Connection value = getConnectionFactory().createConnection();
            if (value instanceof EnhancedConnection) {
                connection = (EnhancedConnection) value;
            }
            else {
                throw new IllegalArgumentException("Created JMS Connection is not an EnhancedConnection: " + value);
            }
        }
        connection.start();
        DestinationSource source = connection.getDestinationSource();
        source.setDestinationListener(new DestinationListener() {
            public void onDestinationEvent(DestinationEvent event) {
                try {
                    ActiveMQDestination destination = event.getDestination();
                    if (destination instanceof ActiveMQQueue) {
                        ActiveMQQueue queue = (ActiveMQQueue) destination;
                        if (event.isAddOperation()) {
                            addQueue(queue);
                        }
                        else {
                            removeQueue(queue);
                        }
                    }
                    else if (destination instanceof ActiveMQTopic) {
                      ActiveMQTopic topic = (ActiveMQTopic) destination;
                      if (event.isAddOperation()) {
                          addTopic(topic);
                      }
                      else {
                          removeTopic(topic);
                      }
                    }
                }
                catch (Exception e) {
                    LOG.warn("Caught: " + e, e);
                }
            }
        });

        Set<ActiveMQQueue> queues = source.getQueues();
        for (ActiveMQQueue queue : queues) {
            addQueue(queue);
        }

        Set<ActiveMQTopic> topics = source.getTopics();
        for (ActiveMQTopic topic : topics) {
            addTopic(topic);
        }
    }


    /**
     *
     * @throws Exception
     * @org.apache.xbean.DestroyMethod
     */
    @PreDestroy
    public void destroy() throws Exception {
        if (connection != null) {
            connection.close();
            connection = null;
        }
    }

    // Properties
    //-------------------------------------------------------------------------
    public CamelContext getCamelContext() {
        return camelContext;
    }

    public void setCamelContext(CamelContext camelContext) {
        this.camelContext = camelContext;
    }

    public EnhancedConnection getConnection() {
        return connection;
    }

    public ConnectionFactory getConnectionFactory() {
        if (connectionFactory == null
                && getComponent().getConfiguration() instanceof ActiveMQConfiguration) {
            connectionFactory = ((ActiveMQConfiguration) getComponent()
                    .getConfiguration()).createConnectionFactory();
        }
        return connectionFactory;
    }

    public void setConnectionFactory(ConnectionFactory connectionFactory) {
        this.connectionFactory = connectionFactory;
    }

    public ActiveMQComponent getComponent() {
        if (component == null) {
            component = camelContext.getComponent("activemq", ActiveMQComponent.class);
        }
        return component;
    }

    public void setComponent(ActiveMQComponent component) {
        this.component = component;
    }

    // Implementation methods
    //-------------------------------------------------------------------------

    protected void addQueue(ActiveMQQueue queue) throws Exception {
        String queueUri = getQueueUri(queue);
        ActiveMQComponent jmsComponent = getComponent();
        Endpoint endpoint = new JmsQueueEndpoint(queueUri, jmsComponent, queue.getPhysicalName(), jmsComponent.getConfiguration());
        camelContext.addEndpoint(queueUri, endpoint);
    }

    protected String getQueueUri(ActiveMQQueue queue) {
        return "activemq:" + queue.getPhysicalName();
    }

    protected void removeQueue(ActiveMQQueue queue) throws Exception {
        String queueUri = getQueueUri(queue);
        // lur cache of endpoints so they will disappear in time
        // this feature needs a new component api - list available endpoints
        camelContext.removeEndpoints(queueUri);
    }

    protected void addTopic(ActiveMQTopic topic) throws Exception {
        String topicUri = getTopicUri(topic);
        ActiveMQComponent jmsComponent = getComponent();
        Endpoint endpoint = new JmsEndpoint(topicUri, jmsComponent, topic.getPhysicalName(), true, jmsComponent.getConfiguration());
        camelContext.addEndpoint(topicUri, endpoint);
    }

    protected String getTopicUri(ActiveMQTopic topic) {
        return "activemq:topic:" + topic.getPhysicalName();
    }

    protected void removeTopic(ActiveMQTopic topic) throws Exception {
        String topicUri = getTopicUri(topic);
        // lur cache of endpoints so they will disappear in time
        // this feature needs a new component api - list available endpoints
        camelContext.removeEndpoints(topicUri);
    }
}

Other ActiveMQ examples (source code examples)

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

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