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ActiveMQ example source code file (AMQ1866.java)

This example ActiveMQ source code file (AMQ1866.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

activemq_broker_uri, activemqconnectionfactory, activemqconnectionfactory, activemqqueue, amqpersistenceadapter, atomiclong, consumer-1, consumerthread, consumerthread, exception, exception, override, thread, thread, util

The ActiveMQ AMQ1866.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.bugs;

import java.util.ArrayList;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;

import javax.jms.Connection;
import javax.jms.MessageConsumer;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;

import junit.framework.TestCase;

import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.broker.BrokerService;
import org.apache.activemq.broker.region.policy.PolicyEntry;
import org.apache.activemq.broker.region.policy.PolicyMap;
import org.apache.activemq.command.ActiveMQQueue;
import org.apache.activemq.store.amq.AMQPersistenceAdapter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * This is a test case for the issue reported at:
 * https://issues.apache.org/activemq/browse/AMQ-1866
 * 
 * If you have a JMS producer sending messages to multiple fast consumers and 
 * one slow consumer, eventually all consumers will run as slow as 
 * the slowest consumer.  
 */
public class AMQ1866 extends TestCase {

    private static final Logger log = LoggerFactory.getLogger(ConsumerThread.class);
    private BrokerService brokerService;
    private ArrayList<Thread> threads = new ArrayList();
    
    String ACTIVEMQ_BROKER_BIND = "tcp://localhost:61616";    
    String ACTIVEMQ_BROKER_URI = "tcp://localhost:61616";
    
    AtomicBoolean shutdown = new AtomicBoolean();
    private ActiveMQQueue destination;

    @Override
    protected void setUp() throws Exception {
        // Start an embedded broker up.
        brokerService = new BrokerService();
        AMQPersistenceAdapter adaptor = new AMQPersistenceAdapter();
        adaptor.setIndexBinSize(4096);
        brokerService.setPersistenceAdapter(adaptor);
        brokerService.deleteAllMessages();
        
        // A small max page size makes this issue occur faster.
        PolicyMap policyMap = new PolicyMap();
        PolicyEntry pe = new PolicyEntry();
        pe.setMaxPageSize(1);
        policyMap.put(new ActiveMQQueue(">"), pe);
        brokerService.setDestinationPolicy(policyMap);
        
        brokerService.addConnector(ACTIVEMQ_BROKER_BIND);
        brokerService.start();
        destination = new ActiveMQQueue(getName());
    }
    
    @Override
    protected void tearDown() throws Exception {
        // Stop any running threads.
        shutdown.set(true);
        for (Thread t : threads) {
            t.interrupt();
            t.join();
        }        
        brokerService.stop();
    }

    public void testConsumerSlowDownPrefetch0() throws Exception {
        ACTIVEMQ_BROKER_URI = "tcp://localhost:61616?jms.prefetchPolicy.queuePrefetch=0";
        doTestConsumerSlowDown();
    }

    public void testConsumerSlowDownPrefetch10() throws Exception {
        ACTIVEMQ_BROKER_URI = "tcp://localhost:61616?jms.prefetchPolicy.queuePrefetch=10";
        doTestConsumerSlowDown();
    }
    
    public void testConsumerSlowDownDefaultPrefetch() throws Exception {
        ACTIVEMQ_BROKER_URI = "tcp://localhost:61616";
        doTestConsumerSlowDown();
    }

    public void doTestConsumerSlowDown() throws Exception {
        
        // Preload the queue.
        produce(20000);
        
        Thread producer = new Thread() {
            @Override
            public void run() {
                try {
                    while(!shutdown.get()) {
                        produce(1000);
                    }
                } catch (Exception e) {
                }
            }
        };
        threads.add(producer);
        producer.start();
        
        // This is the slow consumer.
        ConsumerThread c1 = new ConsumerThread("Consumer-1");
        threads.add(c1);
        c1.start();

        // Wait a bit so that the slow consumer gets assigned most of the messages.
        Thread.sleep(500);
        ConsumerThread c2 = new ConsumerThread("Consumer-2");
        threads.add(c2);
        c2.start();

        int totalReceived = 0;
        for ( int i=0; i < 30; i++) {
            Thread.sleep(1000);
            long c1Counter = c1.counter.getAndSet(0);
            long c2Counter = c2.counter.getAndSet(0);
            System.out.println("c1: "+c1Counter+", c2: "+c2Counter);
            totalReceived += c1Counter;
            totalReceived += c2Counter;
            
            // Once message have been flowing for a few seconds, start asserting that c2 always gets messages.  It should be receiving about 100 / sec
            if( i > 10 ) {
                assertTrue("Total received=" + totalReceived + ", Consumer 2 should be receiving new messages every second.", c2Counter > 0);
            }
        }
    }    
    
    public void produce(int count) throws Exception {
        Connection connection=null;
        try {
            ActiveMQConnectionFactory factory = new ActiveMQConnectionFactory(ACTIVEMQ_BROKER_URI);
            factory.setDispatchAsync(true);
            
            connection = factory.createConnection();
            
            Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            MessageProducer producer = session.createProducer(destination);
            connection.start();
            
            for( int i=0 ; i< count; i++ ) {
                producer.send(session.createTextMessage(getName()+" Message "+(++i)));
            }
            
        } finally {
            try {
                connection.close();
            } catch (Throwable e) {
            }
        }
    }
    
    public class ConsumerThread extends Thread {
        final AtomicLong counter = new AtomicLong();

        public ConsumerThread(String threadId) {
            super(threadId);
        }

        public void run() {
            Connection connection=null;
            try {
                log.debug(getName() + ": is running");
                
                ActiveMQConnectionFactory factory = new ActiveMQConnectionFactory(ACTIVEMQ_BROKER_URI);
                factory.setDispatchAsync(true);
                
                connection = factory.createConnection();
                
                Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
                MessageConsumer consumer = session.createConsumer(destination);
                connection.start();
                
                while (!shutdown.get()) {
                    TextMessage msg = (TextMessage)consumer.receive(1000);
                    if ( msg!=null ) {
                        int sleepingTime;
                        if (getName().equals("Consumer-1")) {
                            sleepingTime = 1000 * 1000;
                        } else {
                            sleepingTime = 1; 
                        }
                        counter.incrementAndGet();
                        Thread.sleep(sleepingTime);
                    }
                }
                
            } catch (Exception e) {
            } finally {
                log.debug(getName() + ": is stopping");
                try {
                    connection.close();
                } catch (Throwable e) {
                }
            }
        }

    }

}

Other ActiveMQ examples (source code examples)

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