RabbitMQ integration basics in Spring Boot - Mini Project: Build & Apply

RabbitMQ integration basics

📖 Scenario: You are building a simple Spring Boot application that sends and receives messages using RabbitMQ. This is common in real-world apps where different parts communicate asynchronously, like order processing systems.

🎯 Goal: Build a Spring Boot app that defines a RabbitMQ queue, sends a message to it, and listens to receive messages from it.

📋 What You'll Learn

Create a RabbitMQ queue bean named helloQueue with the value hello

Create a configuration property rabbitmqExchange with value helloExchange

Write a method sendMessage in a service to send a message Hello, RabbitMQ! to the queue

Write a listener method receiveMessage that listens to the helloQueue and logs the received message

💡 Why This Matters

🌍 Real World

Many applications use RabbitMQ to decouple components and handle tasks asynchronously, such as sending emails, processing orders, or updating caches.

💼 Career

Understanding RabbitMQ integration with Spring Boot is valuable for backend developers working on scalable, event-driven systems.

1

Define the RabbitMQ queue bean

In your Spring Boot application, create a configuration class called RabbitConfig. Inside it, define a bean method called helloQueue that returns a new Queue with the name "hello".

Spring Boot

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.amqp.core.Queue;

@Configuration
public class RabbitConfig {
    // Define the queue bean here
}

Need a hint?

Use @Bean annotation on a method that returns new Queue("hello").

2

Add a configuration property for the exchange

In the RabbitConfig class, add a public static final String variable called rabbitmqExchange and set it to "helloExchange".

Spring Boot

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.amqp.core.Queue;

@Configuration
public class RabbitConfig {
    @Bean
    public Queue helloQueue() {
        return new Queue("hello");
    }

    // Define rabbitmqExchange variable here
}

Need a hint?

Declare a public static final String variable with the exact name and value.

3

Create a service method to send a message

Create a Spring service class called MessageSender. Inject AmqpTemplate via constructor. Add a method sendMessage that sends the string "Hello, RabbitMQ!" to the queue named "hello" using convertAndSend.

Spring Boot

import org.springframework.stereotype.Service;
import org.springframework.amqp.core.AmqpTemplate;

@Service
public class MessageSender {
    private final AmqpTemplate amqpTemplate;

    public MessageSender(AmqpTemplate amqpTemplate) {
        this.amqpTemplate = amqpTemplate;
    }

    // Add sendMessage method here
}

Need a hint?

Use amqpTemplate.convertAndSend with the queue name and message string.

4

Add a listener method to receive messages

Create a Spring service class called MessageListener. Add a method receiveMessage annotated with @RabbitListener(queues = "hello"). The method should accept a String message parameter and log it using System.out.println with the prefix "Received:".

Spring Boot

import org.springframework.stereotype.Service;
import org.springframework.amqp.rabbit.annotation.RabbitListener;

@Service
public class MessageListener {
    // Add receiveMessage method here
}

Need a hint?

Use @RabbitListener annotation on the method and print the message with the prefix.