Spring Boot + RabbitMQ

POM

<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.example</groupId>
    <artifactId>rabbitmq-demo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <java.version>17</java.version> <!-- Ensure you're using Java 17 or higher -->
        <spring.boot.version>3.3.3</spring.boot.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <version>${spring.boot.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
            <version>${spring.boot.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>${spring.boot.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <version>${spring.boot.version}</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

application.properties

spring.rabbitmq.host=cougar.rmq.cloudamqp.com
spring.rabbitmq.port=5672
spring.rabbitmq.username=your_username
spring.rabbitmq.password=your_password
spring.rabbitmq.virtual-host=your_virtual-host

Application.java

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

RabbitConfig.java

package com.example.demo;
import org.springframework.amqp.core.Queue;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class RabbitConfig {
    public static final String QUEUE_NAME = "demoQueue";

    @Bean
    public Queue demoQueue() {
        return new Queue(QUEUE_NAME, false);
    }
}

MessageProducer.java

package com.example.demo;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.http.ResponseEntity;
import org.springframework.http.HttpStatus;

@RestController
public class MessageProducer {

    @Autowired
    private RabbitTemplate rabbitTemplate;

    @PostMapping("/send")
    public ResponseEntity<String> sendMessage(@RequestBody String message) {
        try {
            rabbitTemplate.convertAndSend(RabbitConfig.QUEUE_NAME, message);
            return ResponseEntity.ok("Message sent: " + message);
        } catch (Exception e) {
            e.printStackTrace(); // Log the error
            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
                                 .body("Failed to send message: " + e.getMessage());
        }
    }
}

MessageConsumer.java

package com.example.demo;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;

@Component
public class MessageConsumer {

    @RabbitListener(queues = RabbitConfig.QUEUE_NAME)
    public void receiveMessage(String message) {
        System.out.println("Received message: " + message);
    }
}

Outcome:

Set Content-Type=application/json

Set body as raw(JSON):

{
    "message": "Hello RabbitMQ!"
}