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Now let”s create a subscriber application which will receive message from the RabbitMQ Topic.
Create Project
Using eclipse, select File → New → Maven Project. Tick the Create a simple project(skip archetype selection) and click Next.
Enter the details, as shown below −
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groupId − com.tutorialspoint
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artifactId − subscriber
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version − 0.0.1-SNAPSHOT
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name − RabbitMQ Subscriber
Click on Finish button and a new project will be created.
pom.xml
Now update the content of pom.xml to include dependencies for RabbitMQ.
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.tutorialspoint.activemq</groupId> <artifactId>subscriber</artifactId> <version>0.0.1-SNAPSHOT</version> <name>RabbitMQ Subscriber</name> <dependencies> <dependency> <groupId>com.rabbitmq</groupId> <artifactId>amqp-client</artifactId> <version>5.14.2</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>1.7.26</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-simple</artifactId> <version>1.7.26</version> </dependency> </dependencies> </project>
Now create a Subscriber class which will receive message from the RabbitMQ Queue.
package com.tutorialspoint.rabbitmq; import java.io.IOException; import java.nio.charset.StandardCharsets; import java.util.concurrent.TimeoutException; import com.rabbitmq.client.Channel; import com.rabbitmq.client.Connection; import com.rabbitmq.client.ConnectionFactory; import com.rabbitmq.client.DeliverCallback; public class Subscriber { private static String EXCHANGE = "MyExchange"; public static void main(String[] args) throws IOException, TimeoutException { ConnectionFactory factory = new ConnectionFactory(); factory.setHost("localhost"); Connection connection = factory.newConnection(); Channel channel = connection.createChannel(); channel.exchangeDeclare(EXCHANGE, "fanout"); String queueName = channel.queueDeclare().getQueue(); channel.queueBind(queueName, EXCHANGE, ""); System.out.println("Waiting for messages. To exit press CTRL+C"); DeliverCallback deliverCallback = (consumerTag, delivery) -> { String message = new String(delivery.getBody(), StandardCharsets.UTF_8); System.out.println("Received ''" + message + "''"); }; channel.basicConsume(queueName, true, deliverCallback, consumerTag -> { }); } }
Subscriber class creates a connection, creates a channel, declares the exchange, create a random queue and binds it with the exchange and then receives message from topic if there is any. Press Ctrl + C to terminate else it will keep polling queue for messages.
We”ll run this application multiple times to create multiple subscribers in RabbitMQ – Test Application chapter.
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