Spring Boot Rabbitmq example

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Introduction to the

Spring Boot RabbitMQ simple program example

Write the details

RabbitMQ docker

To avoid the trouble, start a RabbitMQ file using docker:

docker run -dit --name rabbitmq -p 5672:5672 rabbitmq
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Maven dependency Configuration

      
<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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>Against 2.4.1</version>
        <relativePath/> <! -- lookup parent from repository -->
    </parent>
    <groupId>com.spring.boot.rabbitmq</groupId>
    <artifactId>rabbitmqexample</artifactId>
    <version>0.0.1 - the SNAPSHOT</version>
    <name>rabbitmqexample</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>
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Consumer authoring

Write a consumer class that receives the message and simply prints it. The code looks like this:

import org.springframework.stereotype.Component;

import java.util.concurrent.CountDownLatch;

@Component
public class Receiver {

    private CountDownLatch latch = new CountDownLatch(1);

    public void receiveMessage(String message) {
        System.out.println("Receive < " + message + ">");
        latch.countDown();
    }

    public CountDownLatch getLatch(a) {
        returnlatch; }}Copy the code

Producer writing

To send a message, the code is roughly as follows:

import org.springframework.amqp.rabbit.core.RabbitTemplate; import org.springframework.boot.CommandLineRunner; import org.springframework.stereotype.Component; import java.util.concurrent.TimeUnit; @Component public class Runner implements CommandLineRunner { private final RabbitTemplate rabbitTemplate; private final Receiver receiver; public Runner(Receiver receiver, RabbitTemplate rabbitTemplate) { this.receiver = receiver; this.rabbitTemplate = rabbitTemplate; } @Override public void run(String... args) throws Exception { System.out.println("Sending message ......" ); rabbitTemplate.convertAndSend(RabbitmqexampleApplication.topicExchangeName, "foo.bar.baz", "Hello from RabbitMA!" ); receiver.getLatch().await(10000, TimeUnit.MILLISECONDS); }}Copy the code

The related configuration

Directly in the main function to configure the code as follows:

import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.Queue;
import org.springframework.amqp.core.TopicExchange;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer;
import org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

@SpringBootApplication
public class RabbitmqexampleApplication {

    static final String topicExchangeName = "spring-boot-exchange";

    static final String queueName = "spring-boot";

    @Bean
    Queue queue(a) {
        return new Queue(queueName, false);
    }

    @Bean
    TopicExchange exchange(a) {
        return new TopicExchange(topicExchangeName);
    }

    @Bean
    Binding binding(Queue queue, TopicExchange exchange) {
        return BindingBuilder.bind(queue).to(exchange).with("foo.bar.#");
    }

    @Bean
    MessageListenerAdapter listenerAdapter(Receiver receiver) {
        return new MessageListenerAdapter(receiver, "receiveMessage");
    }

    @Bean
    SimpleMessageListenerContainer container(ConnectionFactory connectionFactory, MessageListenerAdapter listenerAdapter) {
        SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
        container.setConnectionFactory(connectionFactory);
        container.setQueueNames(queueName);
        container.setMessageListener(listenerAdapter);
        return container;
    }

    public static void main(String[] args) { SpringApplication.run(RabbitmqexampleApplication.class, args).close(); }}Copy the code

You can see the output after you run it