JavaEE 6: How to inject JMS Resource in a standalone JMS client?

Question

I can't get javax.jms.ConnectionFactory injected into my standalone JMS client. I get a java.lang.NullPointerException at connectionFactory.createConnection() in the code below.

JmsClient.java

public class JmsClient {

    @Resource(mappedName="jms/QueueConnectionFactory")
    private static ConnectionFactory connectionFactory;    

    @Resource(mappedName="jms/ShippingRequestQueue")
    private static Destination destination;

    public static void main(String[] args) {        
        try {
            Connection connection = connectionFactory.createConnection();
            connection.start();

            Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
            MessageProducer producer = session.createProducer(destination);
            ObjectMessage message = session.createObjectMessage();

            ShippingRequestQueue shippingRequest = new ShippingRequestQueue(1, "107, Old Street");

            message.setObject(shippingRequest);
            producer.send(message);
            session.close();
            connection.close();

            System.out.println("Shipping request message sent ..");
        } catch (Throwable ex) {
            ex.printStackTrace();
        }        
    }

}

I have created the corresponding Connection Factory and Destination Resource at Open MQ (MoM) using Glassfish 3.1 Admin Console.

Could someone help me understand what am I missing?

Commensurate

@Resource doesn't work but looking up using JNDI name does. Context jndiContext = new InitialContext(); ConnectionFactory connectionFactory = (ConnectionFactory) jndiContext.lookup("jms/QueueConnectionFactory"); Queue destination = (Queue) jndiContext.lookup("jms/ShippingRequestQueue"); – Commensurate

Answer 1

Resource injection works only in a managed environment, such as a Java EE application server, or a Spring container, for instance. In a standalone application JNDI is your only choice.

Annotations in general are meant to be processed by some tool/framework, and plain JVM that executes your main() method simply does not contain such. The only annotations I know of that are processed by JVM out of the box are compile-time @Deprecated, @Override and @SuppressWarnings.

Replying to your comment: I don't have access to the book, so I'll only guess that they probably describe running an application client component and not standalone application client. It's not the same — check Glassfish EJB FAQ. ACCs are normally deployed into an application server and can be executed via Java Web Start or without it, but in an AS-specific way. See Glassfish example (you didn't say what AS your EJB executes in).

Swarm

public class ShippingRequestJMSProducer { @Resource(name = "jms/ShippingRequestQueue", mappedName = "ShippingRequestQueue") private static Destination destination; @Resource(name = "jms/QueueConnectionFactory") private static ConnectionFactory connectionFactory; public static void main(String[] args) { // rest of the code } } . This is a part of the code from chapter 4 from the book EJB 3 in Action. Dependency injection of resources are being done in this standalone client. How does it work? – Commensurate

Right. With gf-client.jar in build path you could only use the lookup method with JNDI name to get to resources. But for dependency injection to work in a standalone client it needs to be deployed to an EJB container to get that extra JavaEE juice. ensode.net/glassfish_rich_ejb_clients.html was useful. With Glassfish 3.1 appclient -client myappclient.jar works. Thanks. – Commensurate

Answer 2

@skip: try @Resource(name="jms/QueueConnectionFactory") instead of @Resource(mappedName="jms/QueueConnectionFactory")

name=JNDI name as per javax.annotation.Resource java doc.

Nosepiece

I tried @Resource(lookup="jms/QueueConnectionFactory") as well but still I am getting the same error as mentioned above as I am not able to get the resources injected. – Commensurate

@skip, this is strange. Because if you look at link:- java.sun.com/javaee/5/docs/api/javax/annotation/Resource.html attribute name related to JNDI name. Did you try to resolve this JNDI name explicitly through NamingContext API? – Nosepiece

@ag112- I've tried server specific mappedName, portable name and the new 'lookup' from JavaEE 6 but I am not able to get the resource injected. Only way it worked was when I did the following: Context jndiContext = new InitialContext(); ConnectionFactory connectionFactory = (ConnectionFactory) jndiContext.lookup("jms/QueueConnectionFactory"); Queue destination = (Queue) jndiContext.lookup("jms/ShippingRequestQueue");. I've tried appending java:comp/env appended explicitly with the JNDI names above as well, which I shouldn't, but that doesn't work either. What am I missing here? – Commensurate