ActiveMQ and JMS : Basic steps for novice - activemq

Question

Hi all please give some basic about ActiveMQ with JMS for novice. And configuration steps also.

Answer 1

We are going to create a console based application using multithreading. So create an java project for console application.
Now follow these steps..........
Add javax.jms.jar, activemq-all-5.3.0.jar, log4j-1.2.15.jar to your project library.
(You can download all of above jar files from http://www.jarfinder.com/ .
create a file naming jndi.properties and paste these following texts .. ( Deatils for jndi.properties just Google it)
# START SNIPPET: jndi
java.naming.factory.initial = org.apache.activemq.jndi.ActiveMQInitialContextFactory
# use the following property to configure the default connector
java.naming.provider.url = tcp://localhost:61616
# use the following property to specify the JNDI name the connection factory
# should appear as.
#connectionFactoryNames = connectionFactory, queueConnectionFactory, topicConnectionFactry
connectionFactoryNames = connectionFactory, queueConnectionFactory, topicConnectionFactry
# register some queues in JNDI using the form
# queue.[jndiName] = [physicalName]
queue.MyQueue = example.MyQueue
# register some topics in JNDI using the form
# topic.[jndiName] = [physicalName]
topic.MyTopic = example.MyTopic
# END SNIPPET: jndi
Add JMSConsumer.java
import javax.jms.*;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
public class JMSConsumer implements Runnable{
private static final Log LOG = LogFactory.getLog(JMSConsumer.class);
public void run() {
Context jndiContext = null;
ConnectionFactory connectionFactory = null;
Connection connection = null;
Session session = null;
MessageConsumer consumer = null;
Destination destination = null;
String sourceName = null;
final int numMsgs;
sourceName= "MyQueue";
numMsgs = 1;
LOG.info("Source name is " + sourceName);
/*
* Create a JNDI API InitialContext object
*/
try {
jndiContext = new InitialContext();
} catch (NamingException e) {
LOG.info("Could not create JNDI API context: " + e.toString());
System.exit(1);
}
/*
* Look up connection factory and destination.
*/
try {
connectionFactory = (ConnectionFactory)jndiContext.lookup("queueConnectionFactory");
destination = (Destination)jndiContext.lookup(sourceName);
} catch (NamingException e) {
LOG.info("JNDI API lookup failed: " + e);
System.exit(1);
}
try {
connection = connectionFactory.createConnection();
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
consumer = session.createConsumer(destination);
connection.start();
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
MessageListener listener = new MyQueueMessageListener();
consumer.setMessageListener(listener );
//Let the thread run for some time so that the Consumer has suffcient time to consume the message
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (JMSException e) {
LOG.info("Exception occurred: " + e);
} finally {
if (connection != null) {
try {
connection.close();
} catch (JMSException e) {
}
}
}
}
}
Add JMSProducer.java
import javax.jms.*;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
public class JMSProducer implements Runnable{
private static final Log LOG = LogFactory.getLog(JMSProducer.class);
public JMSProducer() {
}
//Run method implemented to run this as a thread.
public void run(){
Context jndiContext = null;
ConnectionFactory connectionFactory = null;
Connection connection = null;
Session session = null;
Destination destination = null;
MessageProducer producer = null;
String destinationName = null;
final int numMsgs;
destinationName = "MyQueue";
numMsgs = 5;
LOG.info("Destination name is " + destinationName);
/*
* Create a JNDI API InitialContext object
*/
try {
jndiContext = new InitialContext();
} catch (NamingException e) {
LOG.info("Could not create JNDI API context: " + e.toString());
System.exit(1);
}
/*
* Look up connection factory and destination.
*/
try {
connectionFactory = (ConnectionFactory)jndiContext.lookup("queueConnectionFactory");
destination = (Destination)jndiContext.lookup(destinationName);
} catch (NamingException e) {
LOG.info("JNDI API lookup failed: " + e);
System.exit(1);
}
/*
* Create connection. Create session from connection; false means
* session is not transacted.create producer, set the text message, set the co-relation id and send the message.
*/
try {
connection = connectionFactory.createConnection();
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
producer = session.createProducer(destination);
TextMessage message = session.createTextMessage();
for (int i = 0; i
Add MyQueueMessageListener.java
import java.io.*;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import javax.jms.*;
public class MyQueueMessageListener implements MessageListener {
private static final Log LOG = LogFactory.getLog(MyQueueMessageListener.class);
/**
*
*/
public MyQueueMessageListener() {
// TODO Auto-generated constructor stub
}
/** (non-Javadoc)
* #see javax.jms.MessageListener#onMessage(javax.jms.Message)
* This is called on receving of a text message.
*/
public void onMessage(Message arg0) {
LOG.info("onMessage() called!");
if(arg0 instanceof TextMessage){
try {
//Print it out
System.out.println("Recieved message in listener: " + ((TextMessage)arg0).getText());
System.out.println("Co-Rel Id: " + ((TextMessage)arg0).getJMSCorrelationID());
try {
//Log it to a file
BufferedWriter outFile = new BufferedWriter(new FileWriter("MyQueueConsumer.txt"));
outFile.write("Recieved message in listener: " + ((TextMessage)arg0).getText());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (JMSException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}else{
System.out.println("~~~~Listener : Error in message format~~~~");
}
}
}
Add SimpleApp.java
public class SimpleApp {
//Run the producer first, then the consumer
public static void main(String[] args) throws Exception {
runInNewthread(new JMSProducer());
runInNewthread(new JMSConsumer());
}
public static void runInNewthread(Runnable runnable) {
Thread brokerThread = new Thread(runnable);
brokerThread.setDaemon(false);
brokerThread.start();
}
}
Now run SimpleApp.java class.
All da best. Happy coding.

Answer 2

Here it is a simple junit test for ActiveMQ and Apache Camel. This two technologies works very good together.
If you want more details about the code, you can find a post in my blog:
http://ignaciosuay.com/unit-testing-active-mq/
public class ActiveMQTest extends CamelTestSupport {
#Override
protected CamelContext createCamelContext() throws Exception {
CamelContext camelContext = super.createCamelContext();
ConnectionFactory connectionFactory = new ActiveMQConnectionFactory("vm://localhost?broker.persistent=false");
camelContext.addComponent("activemq", jmsComponentClientAcknowledge(connectionFactory));
return camelContext;
}
#Override
protected RouteBuilder createRouteBuilder() throws Exception {
return new RouteBuilder() {
#Override
public void configure() throws Exception {
from("mina:tcp://localhost:6666?textline=true&sync=false")
.to("activemq:processHL7");
from("activemq:processHL7")
.to("mock:end");
}
};
}
#Test
public void testSendHL7Message() throws Exception {
MockEndpoint mock = getMockEndpoint("mock:end");
String m = "MSH|^~\\&|hl7Integration|hl7Integration|||||ADT^A01|||2.5|\r" +
"EVN|A01|20130617154644\r" +
"PID|1|465 306 5961||407623|Wood^Patrick^^^MR||19700101|1|\r" +
"PV1|1||Location||||||||||||||||261938_6_201306171546|||||||||||||||||||||||||20130617134644|";
mock.expectedBodiesReceived(m);
template.sendBody("mina:tcp://localhost:6666?textline=true&sync=false", m);
mock.assertIsSatisfied();
}