参考文档：连RabbitMQ的5种核心消息模式都不懂，也敢说自己会用消息队列！

1. 简介

RabbitMQ 是最受欢迎的开源消息中间件之一，在全球范围内被广泛应用。RabbitMQ 是轻量级且易于部署的，能支持多种消息协议。RabbitMQ 可以部署在分布式系统中，以满足大规模、高可用的要求。

我们先来了解下 RabbitMQ 中的相关概念，这里以路由模式为例。

2. 简单模式

简单模式是最简单的消息模式，它包含一个生产者、一个消费者和一个队列。生产者向队列里发送消息，消费者从队列中获取消息并消费。

添加简单模式相关 Java 配置，创建一个名为 simple.hello 的队列、一个生产者和一个消费者；

@Configuration
public class SimpleRabbitConfig {

    @Bean
    public Queue hello() {
        return new Queue("simple.hello");
    }

    @Bean
    public SimpleSender simpleSender(){
        return new SimpleSender();
    }

    @Bean
    public SimpleReceiver simpleReceiver(){
        return new SimpleReceiver();
    }

}

生产者通过 send 方法 向队列 simple.hello 中发送消息；

public class SimpleSender {

    private static final Logger LOGGER = LoggerFactory.getLogger(SimpleSender.class);

    @Autowired
    private RabbitTemplate template;

    private static final String queueName="simple.hello";

    public void send() {
        String message = "Hello World!";
        this.template.convertAndSend(queueName, message);
        LOGGER.info(" [x] Sent '{}'", message);
    }

}

消费者从队列 simple.hello 中获取消息；

@RabbitListener(queues = "simple.hello")
public class SimpleReceiver {

    private static final Logger LOGGER = LoggerFactory.getLogger(SimpleReceiver.class);

    @RabbitHandler
    public void receive(String in) {
        LOGGER.info(" [x] Received '{}'", in);
    }

}

在 controller 中添加测试接口，调用该接口开始发送消息；

@Api(tags = "RabbitController", description = "RabbitMQ功能测试")
@Controller
@RequestMapping("/rabbit")
public class RabbitController {

    @Autowired
    private SimpleSender simpleSender;

    @ApiOperation("简单模式")
    @RequestMapping(value = "/simple", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult simpleTest() {
        for(int i=0;i<10;i++){
            simpleSender.send();
            ThreadUtil.sleep(1000);
        }
        return CommonResult.success(null);
    }
}

运行后结果如下，可以发现生产者往队列中发送消息，消费者从队列中获取消息并消费。

3. 工作模式

工作模式是指向多个互相竞争的消费者发送消息的模式，它包含一个生产者、两个消费者和一个队列。两个消费者同时绑定到一个队列上去，当消费者获取消息处理耗时任务时，空闲的消费者从队列中获取并消费消息。

添加工作模式相关 Java 配置，创建一个名为 work.hello 的队列、一个生产者和两个消费者；

@Configuration
public class WorkRabbitConfig {

    @Bean
    public Queue workQueue() {
        return new Queue("work.hello");
    }

    @Bean
    public WorkReceiver workReceiver1() {
        return new WorkReceiver(1);
    }

    @Bean
    public WorkReceiver workReceiver2() {
        return new WorkReceiver(2);
    }

    @Bean
    public WorkSender workSender() {
        return new WorkSender();
    }

}

生产者通过send方法向队列work.hello中发送消息，消息中包含一定数量的.号；

public class WorkSender {

    private static final Logger LOGGER = LoggerFactory.getLogger(WorkSender.class);

    @Autowired
    private RabbitTemplate template;

    private static final String queueName = "work.hello";

    public void send(int index) {
        StringBuilder builder = new StringBuilder("Hello");
        int limitIndex = index % 3+1;
        for (int i = 0; i < limitIndex; i++) {
            builder.append('.');
        }
        builder.append(index+1);
        String message = builder.toString();
        template.convertAndSend(queueName, message);
        LOGGER.info(" [x] Sent '{}'", message);
    }

}

两个消费者从队列work.hello中获取消息，名称分别为instance 1和instance 2，消息中包含.号越多，耗时越长；

@RabbitListener(queues = "work.hello")
public class WorkReceiver {

    private static final Logger LOGGER = LoggerFactory.getLogger(WorkReceiver.class);

    private final int instance;

    public WorkReceiver(int i) {
        this.instance = i;
    }

    @RabbitHandler
    public void receive(String in) {
        StopWatch watch = new StopWatch();
        watch.start();
        LOGGER.info("instance {} [x] Received '{}'", this.instance, in);
        doWork(in);
        watch.stop();
        LOGGER.info("instance {} [x] Done in {}s", this.instance, watch.getTotalTimeSeconds());
    }

    private void doWork(String in) {
        for (char ch : in.toCharArray()) {
            if (ch == '.') {
                ThreadUtil.sleep(1000);
            }
        }
    }

}

在 controller 中添加测试接口，调用该接口开始发送消息；

@Api(tags = "RabbitController", description = "RabbitMQ功能测试")
@Controller
@RequestMapping("/rabbit")
public class RabbitController {

    @Autowired
    private WorkSender workSender;

    @ApiOperation("工作模式")
    @RequestMapping(value = "/work", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult workTest() {
        for(int i=0;i<10;i++){
            workSender.send(i);
            ThreadUtil.sleep(1000);
        }
        return CommonResult.success(null);
    }
}

运行后结果如下，可以发现生产者往队列中发送包含不同数量.号的消息，instance 1和instance 2消费者互相竞争，分别消费了一部分消息。

4. 发布/订阅模式

发布/订阅模式是指同时向多个消费者发送消息的模式（类似广播的形式），它包含一个生产者、两个消费者、两个队列和一个交换机。两个消费者同时绑定到不同的队列上去，两个队列绑定到交换机上去，生产者通过发送消息到交换机，所有消费者接收并消费消息。

添加发布/订阅模式相关Java配置，创建一个名为exchange.fanout的交换机、一个生产者、两个消费者和两个匿名队列，将两个匿名队列都绑定到交换机；

@Configuration
public class FanoutRabbitConfig {

    @Bean
    public FanoutExchange fanout() {
        return new FanoutExchange("exchange.fanout");
    }

    // bean 的默认名字为方法名
    @Bean
    public Queue fanoutQueue1() {
        return new AnonymousQueue();
    }

    @Bean
    public Queue fanoutQueue2() {
        return new AnonymousQueue();
    }

    // 参数名和 bean 方法名一致注入
    @Bean
    public Binding fanoutBinding1(FanoutExchange fanout, Queue fanoutQueue1) {
        return BindingBuilder.bind(fanoutQueue1).to(fanout);
    }

    @Bean
    public Binding fanoutBinding2(FanoutExchange fanout, Queue fanoutQueue2) {
        return BindingBuilder.bind(fanoutQueue2).to(fanout);
    }

    @Bean
    public FanoutReceiver fanoutReceiver() {
        return new FanoutReceiver();
    }

    @Bean
    public FanoutSender fanoutSender() {
        return new FanoutSender();
    }

}

生产者通过send方法向交换机exchange.fanout中发送消息，消息中包含一定数量的.号；

public class FanoutSender {
    private static final Logger LOGGER = LoggerFactory.getLogger(FanoutSender.class);
    @Autowired
    private RabbitTemplate template;

    private static final String exchangeName = "exchange.fanout";

    public void send(int index) {
        StringBuilder builder = new StringBuilder("Hello");
        int limitIndex = index % 3 + 1;
        for (int i = 0; i < limitIndex; i++) {
            builder.append('.');
        }
        builder.append(index + 1);
        String message = builder.toString();
        template.convertAndSend(exchangeName, "", message);
        LOGGER.info(" [x] Sent '{}'", message);
    }

}

消费者从绑定的匿名队列中获取消息，消息中包含.号越多，耗时越长，由于该消费者可以从两个队列中获取并消费消息，可以看做两个消费者，名称分别为instance 1和instance 2；

public class FanoutReceiver {

    private static final Logger LOGGER = LoggerFactory.getLogger(FanoutReceiver.class);

    @RabbitListener(queues = "#{fanoutQueue1.name}")
    public void receive1(String in) {
        receive(in, 1);
    }

    @RabbitListener(queues = "#{fanoutQueue2.name}")
    public void receive2(String in) {
        receive(in, 2);
    }

    private void receive(String in, int receiver) {
        StopWatch watch = new StopWatch();
        watch.start();
        LOGGER.info("instance {} [x] Received '{}'", receiver, in);
        doWork(in);
        watch.stop();
        LOGGER.info("instance {} [x] Done in {}s", receiver, watch.getTotalTimeSeconds());
    }

    private void doWork(String in) {
        for (char ch : in.toCharArray()) {
            if (ch == '.') {
                ThreadUtil.sleep(1000);
            }
        }
    }

}

在controller中添加测试接口，调用该接口开始发送消息；

@Api(tags = "RabbitController", description = "RabbitMQ功能测试")
@Controller
@RequestMapping("/rabbit")
public class RabbitController {

    @Autowired
    private FanoutSender fanoutSender;

    @ApiOperation("发布/订阅模式")
    @RequestMapping(value = "/fanout", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult fanoutTest() {
        for(int i=0;i<10;i++){
            fanoutSender.send(i);
            ThreadUtil.sleep(1000);
        }
        return CommonResult.success(null);
    }
}

运行后结果如下，可以发现生产者往队列中发送包含不同数量.号的消息，instance 1和instance 2同时获取并消费了消息。

5. 路由模式

路由模式是可以根据路由键选择性给多个消费者发送消息的模式，它包含一个生产者、两个消费者、两个队列和一个交换机。两个消费者同时绑定到不同的队列上去，两个队列通过路由键绑定到交换机上去，生产者发送消息到交换机，交换机通过路由键转发到不同队列，队列绑定的消费者接收并消费消息。

添加路由模式相关Java配置，创建一个名为exchange.direct的交换机、一个生产者、两个消费者和两个匿名队列，队列通过路由键都绑定到交换机，队列1的路由键为orange和black，队列2的路由键为green和black；

@Configuration
public class DirectRabbitConfig {

    @Bean
    public DirectExchange direct() {
        return new DirectExchange("exchange.direct");
    }

    @Bean
    public Queue directQueue1() {
        return new AnonymousQueue();
    }

    @Bean
    public Queue directQueue2() {
        return new AnonymousQueue();
    }

    @Bean
    public Binding directBinding1a(DirectExchange direct, Queue directQueue1) {
        return BindingBuilder.bind(directQueue1).to(direct).with("orange");
    }

    @Bean
    public Binding directBinding1b(DirectExchange direct, Queue directQueue1) {
        return BindingBuilder.bind(directQueue1).to(direct).with("black");
    }

    @Bean
    public Binding directBinding2a(DirectExchange direct, Queue directQueue2) {
        return BindingBuilder.bind(directQueue2).to(direct).with("green");
    }

    @Bean
    public Binding directBinding2b(DirectExchange direct, Queue directQueue2) {
        return BindingBuilder.bind(directQueue2).to(direct).with("black");
    }

    @Bean
    public DirectReceiver receiver() {
        return new DirectReceiver();
    }


    @Bean
    public DirectSender directSender() {
        return new DirectSender();
    }

}

生产者通过send方法向交换机exchange.direct中发送消息，发送时使用不同的路由键，根据路由键会被转发到不同的队列；

public class DirectSender {

    @Autowired
    private RabbitTemplate template;

    private static final String exchangeName = "exchange.direct";

    private final String[] keys = {"orange", "black", "green"};

    private static final Logger LOGGER = LoggerFactory.getLogger(DirectSender.class);

    public void send(int index) {
        StringBuilder builder = new StringBuilder("Hello to ");
        int limitIndex = index % 3;
        String key = keys[limitIndex];
        builder.append(key).append(' ');
        builder.append(index+1);
        String message = builder.toString();
        template.convertAndSend(exchangeName, key, message);
        LOGGER.info(" [x] Sent '{}'", message);
    }

}

消费者从自己绑定的匿名队列中获取消息，由于该消费者可以从两个队列中获取并消费消息，可以看做两个消费者，名称分别为instance 1和instance 2；

public class DirectReceiver {
    private static final Logger LOGGER = LoggerFactory.getLogger(DirectReceiver.class);

    @RabbitListener(queues = "#{directQueue1.name}")
    public void receive1(String in){
        receive(in, 1);
    }

    @RabbitListener(queues = "#{directQueue2.name}")
    public void receive2(String in){
        receive(in, 2);
    }

    private void receive(String in, int receiver){
        StopWatch watch = new StopWatch();
        watch.start();
        LOGGER.info("instance {} [x] Received '{}'", receiver, in);
        doWork(in);
        watch.stop();
        LOGGER.info("instance {} [x] Done in {}s", receiver, watch.getTotalTimeSeconds());
    }

    private void doWork(String in){
        for (char ch : in.toCharArray()) {
            if (ch == '.') {
                ThreadUtil.sleep(1000);
            }
        }
    }

}

在controller中添加测试接口，调用该接口开始发送消息；

@Api(tags = "RabbitController", description = "RabbitMQ功能测试")
@Controller
@RequestMapping("/rabbit")
public class RabbitController {

    @Autowired
    private DirectSender directSender;

    @ApiOperation("路由模式")
    @RequestMapping(value = "/direct", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult directTest() {
        for(int i=0;i<10;i++){
            directSender.send(i);
            ThreadUtil.sleep(1000);
        }
        return CommonResult.success(null);
    }
}

运行后结果如下，可以发现生产者往队列中发送包含不同路由键的消息，instance 1获取到了orange和black消息，instance 2获取到了green和black消息。

6. 通配符模式

通配符模式是可以根据路由键匹配规则选择性给多个消费者发送消息的模式，它包含一个生产者、两个消费者、两个队列和一个交换机。两个消费者同时绑定到不同的队列上去，两个队列通过路由键匹配规则绑定到交换机上去，生产者发送消息到交换机，交换机通过路由键匹配规则转发到不同队列，队列绑定的消费者接收并消费消息。

特殊匹配符号

• *：只能匹配一个单词；
• #：可以匹配零个或多个单词。

添加通配符模式相关Java配置，创建一个名为exchange.topic的交换机、一个生产者、两个消费者和两个匿名队列，匹配*.orange.*和*.*.rabbit发送到队列1，匹配lazy.#发送到队列2；

@Configuration
public class TopicRabbitConfig {

    @Bean
    public TopicExchange topic() {
        return new TopicExchange("exchange.topic");
    }

    @Bean
    public Queue topicQueue1() {
        return new AnonymousQueue();
    }

    @Bean
    public Queue topicQueue2() {
        return new AnonymousQueue();
    }

    @Bean
    public Binding topicBinding1a(TopicExchange topic, Queue topicQueue1) {
        return BindingBuilder.bind(topicQueue1).to(topic).with("*.orange.*");
    }

    @Bean
    public Binding topicBinding1b(TopicExchange topic, Queue topicQueue1) {
        return BindingBuilder.bind(topicQueue1).to(topic).with("*.*.rabbit");
    }

    @Bean
    public Binding topicBinding2a(TopicExchange topic, Queue topicQueue2) {
        return BindingBuilder.bind(topicQueue2).to(topic).with("lazy.#");
    }

    @Bean
    public TopicReceiver topicReceiver() {
        return new TopicReceiver();
    }

    @Bean
    public TopicSender topicSender() {
        return new TopicSender();
    }

}

生产者通过send方法向交换机exchange.topic中发送消息，消息中包含不同的路由键；

public class TopicSender {

    @Autowired
    private RabbitTemplate template;

    private static final String exchangeName = "exchange.topic";

    private static final Logger LOGGER = LoggerFactory.getLogger(TopicSender.class);


    private final String[] keys = {"quick.orange.rabbit", "lazy.orange.elephant", "quick.orange.fox",
            "lazy.brown.fox", "lazy.pink.rabbit", "quick.brown.fox"};

    public void send(int index) {
        StringBuilder builder = new StringBuilder("Hello to ");
        int limitIndex = index%keys.length;
        String key = keys[limitIndex];
        builder.append(key).append(' ');
        builder.append(index+1);
        String message = builder.toString();
        template.convertAndSend(exchangeName, key, message);
        LOGGER.info(" [x] Sent '{}'",message);
        System.out.println(" [x] Sent '" + message + "'");
    }

}

消费者从自己绑定的匿名队列中获取消息，由于该消费者可以从两个队列中获取并消费消息，可以看做两个消费者，名称分别为instance 1和instance 2；

public class TopicReceiver {

    private static final Logger LOGGER = LoggerFactory.getLogger(TopicReceiver.class);

    @RabbitListener(queues = "#{topicQueue1.name}")
    public void receive1(String in){
        receive(in, 1);
    }

    @RabbitListener(queues = "#{topicQueue2.name}")
    public void receive2(String in){
        receive(in, 2);
    }

    public void receive(String in, int receiver){
        StopWatch watch = new StopWatch();
        watch.start();
        LOGGER.info("instance {} [x] Received '{}'", receiver, in);
        doWork(in);
        watch.stop();
        LOGGER.info("instance {} [x] Done in {}s", receiver, watch.getTotalTimeSeconds());
    }

    private void doWork(String in){
        for (char ch : in.toCharArray()) {
            if (ch == '.') {
                ThreadUtil.sleep(1000);
            }
        }
    }

}

在controller中添加测试接口，调用该接口开始发送消息；

@Api(tags = "RabbitController", description = "RabbitMQ功能测试")
@Controller
@RequestMapping("/rabbit")
public class RabbitController {

    @Autowired
    private TopicSender topicSender;

    @ApiOperation("通配符模式")
    @RequestMapping(value = "/topic", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult topicTest() {
        for(int i=0;i<10;i++){
            topicSender.send(i);
            ThreadUtil.sleep(1000);
        }
        return CommonResult.success(null);
    }
}

运行后结果如下，可以发现生产者往队列中发送包含不同路由键的消息，instance 1和instance 2分别获取到了匹配的消息。