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ActiveMQ example source code file (VirtualTopic.java)

This example ActiveMQ source code file (VirtualTopic.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

activemqdestination, activemqdestination, activemqqueue, activemqtopic, connectioncontext, consumer, destination, destinationfilter, selectorawarevirtualtopicinterceptor, string, string, virtualtopic, virtualtopic, virtualtopicinterceptor

The ActiveMQ VirtualTopic.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.broker.region.virtual;

import org.apache.activemq.broker.Broker;
import org.apache.activemq.broker.ConnectionContext;
import org.apache.activemq.broker.region.Destination;
import org.apache.activemq.command.ActiveMQDestination;
import org.apache.activemq.command.ActiveMQQueue;
import org.apache.activemq.command.ActiveMQTopic;
import org.apache.activemq.filter.DestinationFilter;

/**
 * Creates <a href="http://activemq.org/site/virtual-destinations.html">Virtual
 * Topics</a> using a prefix and postfix. The virtual destination creates a
 * wildcard that is then used to look up all active queue subscriptions which
 * match.
 * 
 * @org.apache.xbean.XBean
 * 
 * 
 */
public class VirtualTopic implements VirtualDestination {

    private String prefix = "Consumer.*.";
    private String postfix = "";
    private String name = ">";
    private boolean selectorAware = false;


    public ActiveMQDestination getVirtualDestination() {
        return new ActiveMQTopic(getName());
    }

    public Destination intercept(Destination destination) {
        return selectorAware ? new SelectorAwareVirtualTopicInterceptor(destination, getPrefix(), getPostfix()) : 
            new VirtualTopicInterceptor(destination, getPrefix(), getPostfix());
    }
    

    public void create(Broker broker, ConnectionContext context, ActiveMQDestination destination) throws Exception {
        if (destination.isQueue() && destination.isPattern() && broker.getDestinations(destination).isEmpty()) {
            DestinationFilter filter = DestinationFilter.parseFilter(new ActiveMQQueue(prefix + DestinationFilter.ANY_DESCENDENT));
            if (filter.matches(destination)) {
                broker.addDestination(context, destination, false);
            }
        }
    }

    public void remove(Destination destination) {        
    }
    
    // Properties
    // -------------------------------------------------------------------------

    public String getPostfix() {
        return postfix;
    }

    /**
     * Sets any postix used to identify the queue consumers
     */
    public void setPostfix(String postfix) {
        this.postfix = postfix;
    }

    public String getPrefix() {
        return prefix;
    }

    /**
     * Sets the prefix wildcard used to identify the queue consumers for a given
     * topic
     */
    public void setPrefix(String prefix) {
        this.prefix = prefix;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
    
    /**
     * Indicates whether the selectors of consumers are used to determine dispatch
     * to a virtual destination, when true only messages matching an existing 
     * consumer will be dispatched.
     * @param selectorAware when true take consumer selectors into consideration
     */
    public void setSelectorAware(boolean selectorAware) {
        this.selectorAware = selectorAware;
    }
    
    public boolean isSelectorAware() {
        return selectorAware;
    }
}

Other ActiveMQ examples (source code examples)

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

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