RabbitMQ client to subscribe to a queue in WSO2 Message Broker 3.0.0 using Java

Hi All,

WSO2 Message Broker 3.0.0 is a distributed message broker that provides reliable messaging.

This post will explain on how the RabbitMQ java client can be used to subscribe to a queue WSO2 Message Broker 3.0.0 with the help of Maven.

Add the RabbitMQ java client dependency

Add the following dependency the pom.xml file

<dependency>
    <groupId>com.rabbitmq</groupId>
    <artifactId>amqp-client</artifactId>
    <version>3.5.3</version>
</dependency>

The Code

Following is the implementation. See descriptions inline.

// The queue name
String queueName = "MyQueue";

// Creating the AMQP connection string for communication
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
factory.setPort(5672);
factory.setVirtualHost("/carbon");
factory.setUsername("admin");
factory.setPassword("admin");
final Connection connection = factory.newConnection();
final Channel channel = connection.createChannel();

// Creating the queue
channel.queueDeclare(queueName, true, false, false, null);

// Binding the queue to "amq.direct" exchange. Exchanges cannot be declared in WSO2 MB 3.0.0.
channel.queueBind(queueName, "amq.direct", queueName);

// Creating consumer
QueueingConsumer consumer = new QueueingConsumer(channel);
channel.basicConsume(queueName, false, consumer);

// Shutdown hook handler
Runtime.getRuntime().addShutdownHook(new Thread() {
    @Override
    public void run() {
        try {
            // Closing the connection
            channel.close();
            connection.close();
        } catch (IOException e) {
            throw new RuntimeException(e);
        } catch (TimeoutException e) {
            throw new RuntimeException(e);
        }
    }
});

// Accepting messages
while (true) {
    QueueingConsumer.Delivery delivery = consumer.nextDelivery();
    String message = new String(delivery.getBody());

    System.out.println("Message Received : " + message);
}

Click here to download the sample maven project.

References...

• https://www.rabbitmq.com/tutorials/tutorial-three-java.html