Marcin bloguje

Treat this post as a quick cheat sheet with the most common things about JMS I tend to forget :)

Minor glitches encountered during work with embedded broker led to some thoughts about switching to external broker. This is how I configure SMX and AcviteMQ.

Necessary steps:

• change apache-servicemix/conf/servicemix.properties activemq.port to sth else than standard, for example 61626
• change apache-activemq/conf/activemq.xml with this settings:
  • change port, the service listens on:

  • setup separate JMX instance:

• the nicest tool I found for browsing queues and topics is Hermes JMS. Sample config, that connects Hermes to ActiveMQ instance is on the picture below:
• sending simple messages with Hermes is basic, but what if you need to set some headers, send bulk messages, etc. Easy, just use Hermes xml format. Look like this code snippet below and is rather self-explanatory:

  
      
          
              
              
    
      
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• since we use lots of Apache Camel to consume messages, here is a simple way to start broker in your tests:
  • start a broker

            BrokerService broker = new org.apache.activemq.broker.BrokerService();
            broker.setBrokerName("AMQ-1");
            broker.addConnector("tcp://localhost:51616");
            broker.setPersistent(false);
            broker.start();
    

    Notice it has persistance disabled.
  • initialize Camel's JMS component:

        ctx.removeComponent("jms");
        ctx.addComponent("jms", ActiveMQComponent.activeMQComponent("tcp://localhost:51616"));
    

  • if you want to pass messages to reference endpoints, (like ref:input), use this wrapper method:

    private JmsEndpoint createJmsEndpoint(String endpoint) throws JMSException {
            ActiveMQComponent amqc = (ActiveMQComponent) ctx.getComponent("jms");
            JmsEndpoint endp = JmsEndpoint.newInstance(new ActiveMQTopic(endpoint), amqc);
            return endp;
    }
    
    createJmsEndpoint("ESB/XYZ")