JMS messaging implementation
- by Gandalf StormCrow
I've been struggling with this "simple" task for more expirienced people, I'm stuck for 2 days now need help. I've changed things arround like zillion times now, finally I stumbled upon this spring JMS tutorial.
What I want to do, Send a message and receive it. I've been also reading this book chapter 8 on messaging. It really nicely explains 2 type of messaging and there is nice example for publish-and-subscribe type but now example for point-to-point messaging( this is the one I need).
I'm able to send message to the queue on my own, but don't have a clue how to receive thats why I tried with this spring tutorial here is what I've got so far :
SENDER :
package quartz.spring.com.example;
import java.util.HashMap;
import java.util.Map;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.Queue;
import javax.jms.Session;
import org.springframework.jms.core.MessageCreator;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.core.JmsTemplate102;
import org.springframework.jms.core.MessagePostProcessor;
public class JmsQueueSender {
private JmsTemplate jmsTemplate;
private Queue queue;
public void setConnectionFactory(ConnectionFactory cf) {
this.jmsTemplate = new JmsTemplate102(cf, false);
}
public void setQueue(Queue queue) {
this.queue = queue;
}
public void simpleSend() {
this.jmsTemplate.send(this.queue, new MessageCreator() {
public Message createMessage(Session session) throws JMSException {
return session.createTextMessage("hello queue world");
}
});
}
public void sendWithConversion() {
Map map = new HashMap();
map.put("Name", "Mark");
map.put("Age", new Integer(47));
jmsTemplate.convertAndSend("testQueue", map, new MessagePostProcessor() {
public Message postProcessMessage(Message message) throws JMSException {
message.setIntProperty("AccountID", 1234);
message.setJMSCorrelationID("123-00001");
return message;
}
});
}
}
RECEIVER :
package quartz.spring.com.example;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.TextMessage;
public class ExampleListener implements MessageListener {
public void onMessage(Message message) {
if (message instanceof TextMessage) {
try {
System.out.println(((TextMessage) message).getText());
}
catch (JMSException ex) {
throw new RuntimeException(ex);
}
}
else {
throw new IllegalArgumentException("Message must be of type TextMessage");
}
}
}
applicationcontext.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:jee="http://www.springframework.org/schema/jee"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-2.0.xsd">
<bean id="sender" class="quartz.spring.com.example.JmsQueueSender" init-method="sendWithConversion" />
<bean id="receiver" class="quartz.spring.com.example.ExampleListener" init-method="onMessage" />
</beans>
Didn't really know that learning curve for this is so long, I mean the idea is very simple:
Send message to the destination queue
Receive message from the destination queue
To receive messages, you do the following(so does book say):
1 Locate a ConnectionFactory, typically using JNDI.
2 Use the ConnectionFactory to create a Connection.
3 Use the Connection to create a Session.
4 Locate a Destination, typically using JNDI.
5 Use the Session to create a MessageConsumer for that Destination.
Once you’ve done this, methods on the
MessageConsumer enable you to either
query the Destination for messages or
to register for message notification.
Can somebody please direct me towards right direction, is there a tutorial which explains in details how to receive message from the queue?I have the working send message code, didn't post it here because this post is too long as it is.
