【消息队列】RabbitMQ生产者消费者代码案例 ，超详细！

一、文章初衷

初学RabbitMQ网络上的案例零零散散，为了方便初学者更好的学习，整理本篇文章，代码完全真实可用，初学者自行实践！

关于初次学习消息队列我们一定要了解它的应用场景，为什么使用？以及如何去使用？整理本篇文章为了分享给初学者给他提供一个详细案例，如下代码可以直接实践！

消息队列最核心的三个点：解耦、异步、削峰

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二、代码详解

生产者的相关代码

/**
 * 编写消息的生产者
 */
@Component
public class MsgProducer implements RabbitTemplate.ConfirmCallback {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    //由于rabbitTemplate的scope属性设置为ConfigurableBeanFactory.SCOPE_PROTOTYPE，所以不能自动注入
    private RabbitTemplate rabbitTemplate;
    /**
     * 构造方法注入rabbitTemplate
     */
    @Autowired
    public MsgProducer(RabbitTemplate rabbitTemplate) {
        this.rabbitTemplate = rabbitTemplate;
        rabbitTemplate.setConfirmCallback(this); //rabbitTemplate如果为单例的话，那回调就是最后设置的内容
    }
     /**
     * 发送消息方法一个交换机配一个路由配一个队列
     * @param content
     */
    public void sendMsg(String content) {
        CorrelationData correlationId = new CorrelationData(UUID.randomUUID().toString());
        //把消息放入ROUTINGKEY_A对应的队列当中去，对应的是队列A
        rabbitTemplate.convertAndSend(RabbitConfig.EXCHANGE_A, RabbitConfig.ROUTINGKEY_A, content, correlationId);
        rabbitTemplate.convertAndSend(RabbitConfig.EXCHANGE_B, RabbitConfig.ROUTINGKEY_B, content, correlationId);
    }

    /**
     * 广播模式
     * @param content
     */
    public void sendAll(String content) {
        rabbitTemplate.convertAndSend("fanoutExchange","", content);
    }

    /**
     * 回调
     */
    @Override
    public void confirm(CorrelationData correlationData, boolean ack, String cause) {
        //logger.info(" 回调id:" + correlationData);
        if (ack) {
            logger.info("消息成功消费");
        } else {
            logger.info("消息消费失败:" + cause);
        }
    }
}

关于Controller层的相关代码

@RestController
public class SendController {

    @Autowired
    private MsgProducer msgProducer;

    @RequestMapping(value = "/send",method = RequestMethod.GET)
    public void send(int length){
        for (int i=1;i<=length;i++){
            msgProducer.sendMsg("这是我发送的第"+i+"个信息");
        }
    }

    @RequestMapping(value = "/sendAll",method = RequestMethod.GET)
    public void sendAll(int length){
        for (int i=1;i<=length;i++){
            msgProducer.sendAll("这是我发送的第"+i+"个信息");
        }
    }
}

消费者的相关代码

@Component
@RabbitListener(queues = RabbitConfig.QUEUE_A)
public class MsgReceiver_one {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    @RabbitHandler
    public void process(String content) {
        logger.info("消费者one接收处理队列A当中的消息： " + content);
    }
}

这两个分别监听队列A和队列B

@Component
@RabbitListener(queues = RabbitConfig.QUEUE_B)
public class MsgReceiver_two {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    @RabbitHandler
    public void process(String content) {
        logger.info("消费者two接收处理队列A当中的消息： " + content);
    }
}

测试：在浏览器输入访问第一个路径输入相关参数

这里第一个路径是生产者分别发送给队列A和B

看到控制台打印相关信息

测试：在浏览器输入访问第二个路径和输入相关参数

这里第二个路径是以广播的形式发布都可以消费

看到控制台打印相关信息

 

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项目配置文件的相关信息

@Configuration
public class RabbitConfig {

    @Value("${spring.rabbitmq.host}")
    private String host;

    @Value("${spring.rabbitmq.port}")
    private int port;

    @Value("${spring.rabbitmq.username}")
    private String username;

    @Value("${spring.rabbitmq.password}")
    private String password;

    public static final String FANOUT_EXCHANGE="fanoutExchange";

    //交换机
    public static final String EXCHANGE_A = "my-mq-exchange_A";
    public static final String EXCHANGE_B = "my-mq-exchange_B";
    public static final String EXCHANGE_C = "my-mq-exchange_C";
    //队列
    public static final String QUEUE_A = "QUEUE_A";
    public static final String QUEUE_B = "QUEUE_B";
    public static final String QUEUE_C = "QUEUE_C";
    //路由关键字 key
    public static final String ROUTINGKEY_A = "spring-boot-routingKey_A";
    public static final String ROUTINGKEY_B = "spring-boot-routingKey_B";
    public static final String ROUTINGKEY_C = "spring-boot-routingKey_C";

    @Bean
    public ConnectionFactory connectionFactory() {
        CachingConnectionFactory connectionFactory = new CachingConnectionFactory(host,port);
        connectionFactory.setUsername(username);
        connectionFactory.setPassword(password);
        //connectionFactory.setVirtualHost("/test");
        connectionFactory.setPublisherConfirms(true);
        return connectionFactory;
    }

    @Bean
    @Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
    //必须是prototype类型
    public RabbitTemplate rabbitTemplate() {
        RabbitTemplate template = new RabbitTemplate(connectionFactory());
        return template;
    }

    /**
     * 针对消费者配置
     * 1. 设置交换机类型
     * 2. 将队列绑定到交换机
     FanoutExchange: 将消息分发到所有的绑定队列，无routingkey的概念
     HeadersExchange ：通过添加属性key-value匹配
     DirectExchange:按照routingkey分发到指定队列
     TopicExchange:多关键字匹配
     */
    @Bean
    public DirectExchange defaultExchangeA() {
        return new DirectExchange(EXCHANGE_A);
    }

    @Bean
    public DirectExchange defaultExchangeB() {
        return new DirectExchange(EXCHANGE_B);
    }

    @Bean
    public DirectExchange directExchangeC(){
        return new DirectExchange(EXCHANGE_C);
    }

    /**
     * 获取队列A
     * @return
     */
    @Bean
    public Queue queueA() {
        return new Queue(QUEUE_A, true); //队列持久
    }

    @Bean
    public Queue queueB() {
        return new Queue(QUEUE_B, true); //队列持久
    }

    @Bean
    public Queue queueC() {
        return new Queue(QUEUE_C, true); //队列持久
    }

    /**
     * 队列绑定交换机
     * @return
     */
    @Bean
    public Binding bindingA() {
        return BindingBuilder.bind(queueA()).to(defaultExchangeA()).with(RabbitConfig.ROUTINGKEY_A);
    }

    @Bean
    public Binding bindingB(){
        return BindingBuilder.bind(queueB()).to(defaultExchangeB()).with(RabbitConfig.ROUTINGKEY_B);
    }

    @Bean
    public Binding bindingC(){
        return BindingBuilder.bind(queueC()).to(directExchangeC()).with(RabbitConfig.ROUTINGKEY_C);
    }

    //配置fanout_exchange
    //fanout只能支持统一广播
    @Bean
    FanoutExchange fanoutExchange() {
        return new FanoutExchange(RabbitConfig.FANOUT_EXCHANGE);
    }

    //把所有的队列都绑定到这个交换机上去
    @Bean
    Binding bindingExchangeA(FanoutExchange fanoutExchange) {
        return BindingBuilder.bind(queueA()).to(fanoutExchange);
    }
    @Bean
    Binding bindingExchangeB(FanoutExchange fanoutExchange) {
        return BindingBuilder.bind(queueB()).to(fanoutExchange);
    }
    @Bean
    Binding bindingExchangeC(FanoutExchange fanoutExchange) {
        return BindingBuilder.bind(queueC()).to(fanoutExchange);
    }
}

RabbitMQ案例小结

1.首先创建一个配置类 然后 创建队列

2.创建生产者 生产者要用消息队列的对象，然后传递你想传递的消息

3.创建控制层 填好路径 ，创建生产者对象，然后发送信息

4.消费者，填写好消费队列的名称，监听准备开始消费