Using ActiveMQ via JNDI

问题:

I'm trying to create simply connect with ActiveMQ using JNDI.

---

I have

1. Queue named 'example.A'.

2. According ActiveMQ documentation touching JNDI, if I want to use ConectionFactories and Queues (Topics) via JNDI, I have to place jndi.properties file on my classpath. As I have understood, activeMQ classpath is %activemq%/conf directory by default. I have not changed it. So I have this property for my queue:

   queue.MyQueue = example.A

3. I have created java client class for ActiveMQ which uses JNDI as below:

       Properties jndiParameters = new Properties() ;
       jndiParameters.put(Context.INITIAL_CONTEXT_FACTORY, "org.apache.activemq.jndi.ActiveMQInitialContextFactory");
       jndiParameters.put(Context.PROVIDER_URL, "tcp://localhost:61616");
       Context context = new InitialContext(jndiParameters);
       ConnectionFactory connectionFactory = (ConnectionFactory) context.lookup("ConnectionFactory");
       Queue queue = (Queue) context.lookup("MyQueue");
   

but it cannot find my queue, it throws exception: javax.naming.NameNotFoundException: MyQueue

Where are my misstakes?

回答1:

The problem is that you are explicitly creating the properties and passing them into the InitialContext constructor. This means the jndi.properties on the class path won't be read.

Your code should be something like:

Context context = new InitialContext();
ConnectionFactory connectionFactory = (ConnectionFactory) context.lookup("ConnectionFactory");
Queue queue = (Queue) context.lookup("MyQueue");

回答2:

You can set static properties as well as retrieve them from a file as such:

    InputStream is = getClass().getResourceAsStream("/my.jndi.properties");
    Properties jndiParameters = new Properties();
    jndiParameters.load(is);
    jndiParameters.put(Context.INITIAL_CONTEXT_FACTORY, "org.apache.activemq.jndi.ActiveMQInitialContextFactory");
    jndiParameters.put(Context.PROVIDER_URL, "tcp://localhost:61616");
    Context ctx =  new InitialContext(jndiParameters);
...

This works as long as you set the static props after you load the resource. Helpful if you're loading the provider url from somewhere else for instance.