配置类
@Configuration
public class TtlQueueConfig {
// 普通交换机名称
public static final String X_EXCHANGE = "X";
// 死信交换机名称
public static final String Y_DEAD_LETTER_EXCHANGE = "Y";
// 普通队列名称
public static final String Queue_A = "QA";
// 死信队列名称
public static final String Queue_B = "QB";
// 死信队列名称
public static final String DEAD_LETTER_QUEUE = "QD";
// 普通队列的名称
public static final String QUEUE_C="QC";
// 声明xExchange
@Bean("xExchange")
public DirectExchange xExchange() {
return new DirectExchange(X_EXCHANGE);
}
// 声明yExchange别名
@Bean("yExchange")
public DirectExchange yExchange() {
return new DirectExchange(Y_DEAD_LETTER_EXCHANGE);
}
// 声明普通队列 TTL为10s钟
@Bean("queueA")
public Queue queueA() {
Map<String, Object> arguments = new HashMap<>();
// 设置死信交换机
arguments.put("x-dead-letter-exchange", Y_DEAD_LETTER_EXCHANGE);
// 设置死信RoutingKey
arguments.put("x-dead-letter-routing-key", "YD");
// 设置TTL
arguments.put("x-message-ttl", 10000);
return QueueBuilder.durable(Queue_A).withArguments(arguments).build();
}
// 声明普通队列TTL 40S
@Bean("queueB")
public Queue queueB() {
Map<String, Object> arguments = new HashMap<>();
// 设置死信交换机
arguments.put("x-dead-letter-exchange", Y_DEAD_LETTER_EXCHANGE);
// 设置死信RoutingKey
arguments.put("x-dead-letter-routing-key", "YD");
// 设置TTL
arguments.put("x-message-ttl", 40000);
return QueueBuilder.durable(Queue_B).withArguments(arguments).build();
}
// 死信队列
@Bean("queueD")
public Queue queueD(){
return QueueBuilder.durable(DEAD_LETTER_QUEUE).build();
}
// 声明QC
@Bean("queueC")
public Queue queueC(){
HashMap<String, Object> arguments = new HashMap<>();
// 设置死信交换机
arguments.put("x-dead-letter-exchange",Y_DEAD_LETTER_EXCHANGE);
// 设置死信RoutingKey
arguments.put("x-dead-letter-routing-key","YD");
return QueueBuilder.durable(QUEUE_C).withArguments(arguments).build();
}
@Bean
public Binding queueCBindingX(@Qualifier("queueC") Queue queueC,
@Qualifier("xExchange") DirectExchange xExchange){
return BindingBuilder.bind(queueC).to(xExchange).with("XC");
}
// 绑定
@Bean
public Binding queueABindingX(@Qualifier("queueA") Queue queueA,
@Qualifier("xExchange") DirectExchange xExchange){
return BindingBuilder.bind(queueA).to(xExchange).with("XA");
}
// 绑定
@Bean
public Binding queueBBindingX(@Qualifier("queueB") Queue queueB,
@Qualifier("xExchange") DirectExchange xExchange){
return BindingBuilder.bind(queueB).to(xExchange).with("XB");
}
@Bean
public Binding queueBBindingY(@Qualifier("queueD") Queue queueD,
@Qualifier("yExchange") DirectExchange yExchange){
return BindingBuilder.bind(queueD).to(yExchange).with("YD");
}
}
死信队列消费者
@Slf4j
@Component
public class DeadLetterQueueConsumer {
// 接收消息
@RabbitListener(queues = "QD")
public void receiveD(Message message, Channel channel){
String msg=new String(message.getBody());
log.info("当前时间:{},收到死信队列的消息:{}",new Date().toString(),msg);
}
}
生产者
@Slf4j
@RestController
@RequestMapping("/ttl")
public class SendMsgController {
@Resource
private RabbitTemplate rabbitTemplate;
@GetMapping("/sendMsg/{message}")
public void sendMsg(@PathVariable String message) {
log.info("当前时间:{},发送一条消息给两个ttl队列:{}", new Date().toString(), message);
rabbitTemplate.convertAndSend("X", "XA", "消息来自ttl为10s的队列" + message);
rabbitTemplate.convertAndSend("X", "XB", "消息来自ttl为40s的队列" + message);
}
@GetMapping("/sendExpirationMsg/{message}/{ttlTime}")
public void sendMsg(@PathVariable String message, @PathVariable String ttlTime) {
log.info("当前时间:{},发送一条时长:{}毫秒消息给QCttl队列:{}", new Date().toString(), ttlTime, message);
rabbitTemplate.convertAndSend("X", "XC", message, msg -> {
// 发送消息的时候 延迟时长
msg.getMessageProperties().setExpiration(ttlTime);
return msg;
});
}
}
application.properties文件
spring.rabbitmq.host=192.168.66.131
spring.rabbitmq.port=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest
优点:
可以动态设置消息的延迟时间,不用每次新增一个需求就增加一个队列
缺点:
由于队列遵循先进先出的原则,如果延迟40s的消息先进队列,紧跟着又进去一个10s的,但是消息是否过期是在即将投递消息到消费者之前判定的,也就是RabbitMQ只会判断队列头部的消息是否过期,其他消息是否过期它是不知道的,所以由于先进去的是40s的,后面10s的才进去,就会造成,消费者消费的时候10s的也是跟着40s的算的,出现消息堆积的情况,虽然10s的已经过期,但是由于40s的先进去,10s的不会被消费掉,之后等40s的消费掉之后,10s的才会出来