RabbitMQ integration with Apache Camel-Kafka-Quarkus connector in Java

18 Sep 2023

RabbitMQ is a popular message broker that provides reliable message delivery between different applications or services. Apache Camel-Kafka-Quarkus connector is a lightweight integration framework that allows seamless integration of RabbitMQ with Apache Kafka and Quarkus applications.

In this blog post, we will explore how to integrate RabbitMQ with Apache Camel-Kafka-Quarkus connector in Java, demonstrating a simple example of sending and consuming messages.

Prerequisites

Before we begin, make sure you have the following prerequisites installed:

JDK 8 or higher
Apache Kafka
RabbitMQ server

Set up the Project

We will start by setting up a new Quarkus project using Maven. Open a terminal and execute the following command:

mvn io.quarkus:quarkus-maven-plugin:1.13.7.Final:create -DprojectGroupId=com.example -DprojectArtifactId=rabbitmq-integration -DprojectVersion=1.0-SNAPSHOT -DclassName="com.example.RabbitMQIntegrationResource" -Dextensions="kafka,quartz,rabbitmq"

This command will create a new Quarkus project with the necessary dependencies for Kafka, Quartz, and RabbitMQ.

Configure RabbitMQ Connection

In the application.properties file, configure the RabbitMQ connection properties:

quarkus.rabbitmq.username=admin
quarkus.rabbitmq.password=admin123
quarkus.rabbitmq.host=localhost
quarkus.rabbitmq.port=5672
quarkus.rabbitmq.virtual-host=/

Make sure to adjust the values according to your RabbitMQ server configuration.

Implement Message Producer

Next, we’ll implement the message producer class, responsible for sending messages to RabbitMQ. Create a new class RabbitMQProducer:

import javax.enterprise.context.ApplicationScoped;

import org.apache.camel.ProducerTemplate;

@ApplicationScoped
public class RabbitMQProducer {

    @Inject
    private ProducerTemplate producerTemplate;

    public void sendMessage(String message) {
        producerTemplate.sendBody("rabbitmq:my-exchange?routingKey=my-queue", message);
    }
}

The sendMessage method sends a message to RabbitMQ exchange named “my-exchange” with a routing key “my-queue”. Adjust these values based on your RabbitMQ setup.

Implement Message Consumer

Now let’s implement the message consumer class that will consume messages from RabbitMQ. Create a new class RabbitMQConsumer:

import javax.enterprise.context.ApplicationScoped;

import org.apache.camel.builder.RouteBuilder;

@ApplicationScoped
public class RabbitMQConsumer extends RouteBuilder {

    @Override
    public void configure() throws Exception {
        from("rabbitmq:my-exchange?queue=my-queue")
            .to("log:received")
            .bean(this, "processMessage");
    }

    public void processMessage(String message) {
        // process the received message
    }
}

The configure method sets up a route to consume messages from the RabbitMQ exchange named “my-exchange” with a queue named “my-queue”. Adjust these values according to your RabbitMQ configuration. The received messages will be logged and passed to the processMessage method for further processing.

Use the Producer and Consumer

Finally, let’s use our producer and consumer classes to send and consume messages. Modify the RabbitMQIntegrationResource class as follows:

import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;

@Path("/rabbitmq")
public class RabbitMQIntegrationResource {

    @Inject
    private RabbitMQProducer producer;

    @GET
    @Path("/send")
    public void sendMessage() {
        producer.sendMessage("Hello, RabbitMQ!");
    }
}

Now, when you access the /rabbitmq/send endpoint, a message will be sent to RabbitMQ.

To consume the messages, you can run the Quarkus application and monitor the logs for the “received” message.

Conclusion

In this blog post, we explored how to integrate RabbitMQ with the Apache Camel-Kafka-Quarkus connector in Java. We set up a Quarkus project, configured the RabbitMQ connection, implemented a message producer, and consumed messages using a message consumer. With this integration, you can easily exchange messages between your applications or services using RabbitMQ as the message broker.

Give it a try and unleash the power of RabbitMQ integration in your Java applications!