ActiveMQ MapMessage receive message with empty theTable

Question

I'm using ActiveMQ 5.9.0 for sending and receiving JMS. First I send MapMessage in a queue:

ConnectionFactory connectionFactory = new ActiveMQConnectionFactory();

Connection connection = connectionFactory.createConnection();
connection.start();

Session session = connection.createSession(Boolean.TRUE, Session.AUTO_ACKNOWLEDGE);
Destination destination = session.createQueue("my-queue");

MessageProducer producer = session.createProducer(destination);
MapMessage message = session.createMapMessage();
message.setDouble(key, value);
producer.send(message);
session.commit();
session.close();
connection.close();
System.out.println(message);

What it prints out is:

ActiveMQMapMessage {commandId = 0, responseRequired = false, messageId = ID:LT006632-52708-1382520875674-11:1:1:1:1, originalDestination = null, originalTransactionId = null, producerId = null, destination = queue://my-queue, transactionId = TX:ID:LT006632-52708-1382520875674-11:1:1, expiration = 0, timestamp = 1382520891291, arrival = 0, brokerInTime = 0, brokerOutTime = 0, correlationId = null, replyTo = null, persistent = true, type = null, priority = 4, groupID = null, groupSequence = 0, targetConsumerId = null, compressed = false, userID = null, content = org.apache.activemq.util.ByteSequence@33cf4, marshalledProperties = null, dataStructure = null, redeliveryCounter = 0, size = 0, properties = null, readOnlyProperties = false, readOnlyBody = false, droppable = false, jmsXGroupFirstForConsumer = false} ActiveMQMapMessage{ theTable = {entry 6=922.0} }

with a correct theTable in the Message.

It receives message in another project in this way:

ConnectionFactory connectionFactory = new ActiveMQConnectionFactory();

Connection connection = connectionFactory.createConnection();
connection.start();

final Session session = connection.createSession(Boolean.TRUE, Session.AUTO_ACKNOWLEDGE);
Destination destination = session.createQueue("my-queue");

MessageConsumer consumer = session.createConsumer(destination);

consumer.setMessageListener(new MessageListener() {

    public void onMessage(Message msg) {
        MapMessage message = (MapMessage) msg;
        // TODO something....
        try {
            System.out.println(message.getJMSType());
            session.commit();
        } catch (JMSException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

});
Thread.sleep(30000);

session.close();
connection.close();

But on receiving the messages it prints out:

ActiveMQMapMessage {commandId = 6, responseRequired = false, messageId = ID:LT006632-52708-1382520875674-11:1:1:1:1, originalDestination = null, originalTransactionId = null, producerId = ID:LT006632-52708-1382520875674-11:1:1:1, destination = queue://my-queue, transactionId = TX:ID:LT006632-52708-1382520875674-11:1:1, expiration = 0, timestamp = 1382520891291, arrival = 0, brokerInTime = 1382520891291, brokerOutTime = 1382520891298, correlationId = null, replyTo = null, persistent = true, type = null, priority = 4, groupID = null, groupSequence = 0, targetConsumerId = null, compressed = false, userID = null, content = org.apache.activemq.util.ByteSequence@186db54, marshalledProperties = null, dataStructure = null, redeliveryCounter = 0, size = 0, properties = null, readOnlyProperties = true, readOnlyBody = true, droppable = false, jmsXGroupFirstForConsumer = false} ActiveMQMapMessage{ theTable = {} }

With an empty theTable item. I'd like to know what's the cause of it and how to solve this problem. Thanks!

Mayoares Mayoares · Accepted Answer · 2013-10-23T12:30:45

We use ActiveMQ 5.8.0, but have same "problem": logging message after receiving doesn't print out 'theTable' entries.

BUT after parsing the map message and logging it again, it DOES print 'theTable' entries!

It seems that you somehow have to 'touch' the message or access its content to print 'theTable' entries. That works at least for us.

ActiveMQ MapMessage receive message with empty theTable

2 Answers