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ActiveMQ example source code file (ConsumerTool.java)

This example ActiveMQ source code file (ConsumerTool.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

consumertool, consumertool, io, ioexception, iterator, jmsexception, message, messageconsumer, session, session, session_transacted, string, string, textmessage, textmessage, util

The ActiveMQ ConsumerTool.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.
 */

import java.io.IOException;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.Iterator;

import javax.jms.Connection;
import javax.jms.DeliveryMode;
import javax.jms.Destination;
import javax.jms.ExceptionListener;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.jms.Topic;

import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;

/**
 * A simple tool for consuming messages
 * 
 * 
 */
public class ConsumerTool extends Thread implements MessageListener, ExceptionListener {

    private boolean running;

    private Session session;
    private Destination destination;
    private MessageProducer replyProducer;

    private boolean pauseBeforeShutdown = false;
    private boolean verbose = true;
    private int maxiumMessages;
    private static int parallelThreads = 1;
    private String subject = "TOOL.DEFAULT";
    private boolean topic;
    private String user = ActiveMQConnection.DEFAULT_USER;
    private String password = ActiveMQConnection.DEFAULT_PASSWORD;
    private String url = ActiveMQConnection.DEFAULT_BROKER_URL;
    private boolean transacted;
    private boolean durable;
    private String clientId;
    private int ackMode = Session.AUTO_ACKNOWLEDGE;
    private String consumerName = "James";
    private long sleepTime;
    private long receiveTimeOut;
	private long batch = 10; // Default batch size for CLIENT_ACKNOWLEDGEMENT or SESSION_TRANSACTED
	private long messagesReceived = 0;

    public static void main(String[] args) {
        ArrayList<ConsumerTool> threads = new ArrayList();
        ConsumerTool consumerTool = new ConsumerTool();
        String[] unknown = CommandLineSupport.setOptions(consumerTool, args);
        if (unknown.length > 0) {
            System.out.println("Unknown options: " + Arrays.toString(unknown));
            System.exit(-1);
        }
        consumerTool.showParameters();
        for (int threadCount = 1; threadCount <= parallelThreads; threadCount++) {
            consumerTool = new ConsumerTool();
            CommandLineSupport.setOptions(consumerTool, args);
            consumerTool.start();
            threads.add(consumerTool);
        }

        while (true) {
            Iterator<ConsumerTool> itr = threads.iterator();
            int running = 0;
            while (itr.hasNext()) {
                ConsumerTool thread = itr.next();
                if (thread.isAlive()) {
                    running++;
                }
            }

            if (running <= 0) {
                System.out.println("All threads completed their work");
                break;
            }

            try {
                Thread.sleep(1000);
            } catch (Exception e) {
            }
        }
        Iterator<ConsumerTool> itr = threads.iterator();
        while (itr.hasNext()) {
            ConsumerTool thread = itr.next();
        }
    }

    public void showParameters() {
        System.out.println("Connecting to URL: " + url);
        System.out.println("Consuming " + (topic ? "topic" : "queue") + ": " + subject);
        System.out.println("Using a " + (durable ? "durable" : "non-durable") + " subscription");
        System.out.println("Running " + parallelThreads + " parallel threads");
    }

    public void run() {
        try {
            running = true;

            ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory(user, password, url);
            Connection connection = connectionFactory.createConnection();
            if (durable && clientId != null && clientId.length() > 0 && !"null".equals(clientId)) {
                connection.setClientID(clientId);
            }
            connection.setExceptionListener(this);
            connection.start();

            session = connection.createSession(transacted, ackMode);
            if (topic) {
                destination = session.createTopic(subject);
            } else {
                destination = session.createQueue(subject);
            }

            replyProducer = session.createProducer(null);
            replyProducer.setDeliveryMode(DeliveryMode.NON_PERSISTENT);

            MessageConsumer consumer = null;
            if (durable && topic) {
                consumer = session.createDurableSubscriber((Topic) destination, consumerName);
            } else {
                consumer = session.createConsumer(destination);
            }

            if (maxiumMessages > 0) {
                consumeMessagesAndClose(connection, session, consumer);
            } else {
                if (receiveTimeOut == 0) {
                    consumer.setMessageListener(this);
                } else {
                    consumeMessagesAndClose(connection, session, consumer, receiveTimeOut);
                }
            }

        } catch (Exception e) {
            System.out.println("[" + this.getName() + "] Caught: " + e);
            e.printStackTrace();
        }
    }

    public void onMessage(Message message) {

		messagesReceived++;

        try {

            if (message instanceof TextMessage) {
                TextMessage txtMsg = (TextMessage) message;
                if (verbose) {

                    String msg = txtMsg.getText();
                    int length = msg.length();
                    if (length > 50) {
                        msg = msg.substring(0, 50) + "...";
                    }
                    System.out.println("[" + this.getName() + "] Received: '" + msg + "' (length " + length + ")");
                }
            } else {
                if (verbose) {
                    System.out.println("[" + this.getName() + "] Received: '" + message + "'");
                }
            }

            if (message.getJMSReplyTo() != null) {
                replyProducer.send(message.getJMSReplyTo(), session.createTextMessage("Reply: " + message.getJMSMessageID()));
            }

            if (transacted) {
				if ((messagesReceived % batch) == 0) {
					System.out.println("Commiting transaction for last " + batch + " messages; messages so far = " + messagesReceived);
					session.commit();
				}
            } else if (ackMode == Session.CLIENT_ACKNOWLEDGE) {
				if ((messagesReceived % batch) == 0) {
					System.out.println("Acknowledging last " + batch + " messages; messages so far = " + messagesReceived);
					message.acknowledge();
				}
            }

        } catch (JMSException e) {
            System.out.println("[" + this.getName() + "] Caught: " + e);
            e.printStackTrace();
        } finally {
            if (sleepTime > 0) {
                try {
                    Thread.sleep(sleepTime);
                } catch (InterruptedException e) {
                }
            }
        }
    }

    public synchronized void onException(JMSException ex) {
        System.out.println("[" + this.getName() + "] JMS Exception occured.  Shutting down client.");
        running = false;
    }

    synchronized boolean isRunning() {
        return running;
    }

    protected void consumeMessagesAndClose(Connection connection, Session session, MessageConsumer consumer) throws JMSException,
            IOException {
        System.out.println("[" + this.getName() + "] We are about to wait until we consume: " + maxiumMessages
                + " message(s) then we will shutdown");

        for (int i = 0; i < maxiumMessages && isRunning();) {
            Message message = consumer.receive(1000);
            if (message != null) {
                i++;
                onMessage(message);
            }
        }
        System.out.println("[" + this.getName() + "] Closing connection");
        consumer.close();
        session.close();
        connection.close();
        if (pauseBeforeShutdown) {
            System.out.println("[" + this.getName() + "] Press return to shut down");
            System.in.read();
        }
    }

    protected void consumeMessagesAndClose(Connection connection, Session session, MessageConsumer consumer, long timeout)
            throws JMSException, IOException {
        System.out.println("[" + this.getName() + "] We will consume messages while they continue to be delivered within: " + timeout
                + " ms, and then we will shutdown");

        Message message;
        while ((message = consumer.receive(timeout)) != null) {
            onMessage(message);
        }

        System.out.println("[" + this.getName() + "] Closing connection");
        consumer.close();
        session.close();
        connection.close();
        if (pauseBeforeShutdown) {
            System.out.println("[" + this.getName() + "] Press return to shut down");
            System.in.read();
        }
    }

    public void setAckMode(String ackMode) {
        if ("CLIENT_ACKNOWLEDGE".equals(ackMode)) {
            this.ackMode = Session.CLIENT_ACKNOWLEDGE;
        }
        if ("AUTO_ACKNOWLEDGE".equals(ackMode)) {
            this.ackMode = Session.AUTO_ACKNOWLEDGE;
        }
        if ("DUPS_OK_ACKNOWLEDGE".equals(ackMode)) {
            this.ackMode = Session.DUPS_OK_ACKNOWLEDGE;
        }
        if ("SESSION_TRANSACTED".equals(ackMode)) {
            this.ackMode = Session.SESSION_TRANSACTED;
        }
    }

    public void setClientId(String clientID) {
        this.clientId = clientID;
    }

    public void setConsumerName(String consumerName) {
        this.consumerName = consumerName;
    }

    public void setDurable(boolean durable) {
        this.durable = durable;
    }

    public void setMaxiumMessages(int maxiumMessages) {
        this.maxiumMessages = maxiumMessages;
    }

    public void setPauseBeforeShutdown(boolean pauseBeforeShutdown) {
        this.pauseBeforeShutdown = pauseBeforeShutdown;
    }

    public void setPassword(String pwd) {
        this.password = pwd;
    }

    public void setReceiveTimeOut(long receiveTimeOut) {
        this.receiveTimeOut = receiveTimeOut;
    }

    public void setSleepTime(long sleepTime) {
        this.sleepTime = sleepTime;
    }

    public void setSubject(String subject) {
        this.subject = subject;
    }

    public void setParallelThreads(int parallelThreads) {
        if (parallelThreads < 1) {
            parallelThreads = 1;
        }
        this.parallelThreads = parallelThreads;
    }

    public void setTopic(boolean topic) {
        this.topic = topic;
    }

    public void setQueue(boolean queue) {
        this.topic = !queue;
    }

    public void setTransacted(boolean transacted) {
        this.transacted = transacted;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public void setUser(String user) {
        this.user = user;
    }

    public void setVerbose(boolean verbose) {
        this.verbose = verbose;
    }

    public void setBatch(long batch) {
        this.batch = batch;
    }
}

Other ActiveMQ examples (source code examples)

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

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