【SpringBoot】SpringBoot整合RabbitMQ消息中间件，实现延迟队列和死信队列

import org.springframework.amqp.core.*;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
 
@Configuration
public class RabbitMQConfig {
 
    public static final String DELAY_EXCHANGE_NAME = "delay_exchange";
    public static final String DEAD_LETTER_QUEUE_NAME = "dead_letter_queue";
    public static final String QUEUE_NAME = "sample_queue";
    public static final String ROUTING_KEY = "sample_routing_key";
 
    @Bean
    Queue deadLetterQueue() {
        return QueueBuilder.durable(DEAD_LETTER_QUEUE_NAME)
                .deadLetterExchange(DELAY_EXCHANGE_NAME)
                .deadLetterRoutingKey(ROUTING_KEY)
                .build();
    }
 
    @Bean
    DirectExchange delayExchange() {
        return new DirectExchange(DELAY_EXCHANGE_NAME);
    }
 
    @Bean
    Queue sampleQueue() {
        return QueueBuilder.durable(QUEUE_NAME)
                .build();
    }
 
    @Bean
    Binding bindingDelayExchange(Queue sampleQueue, DirectExchange delayExchange) {
        return BindingBuilder.bind(sampleQueue)
                .to(delayExchange)
                .with(ROUTING_KEY);
    }
 
    @Bean
    Binding bindingDeadLetterQueue(Queue deadLetterQueue, DirectExchange delayExchange) {
        return BindingBuilder.bind(deadLetterQueue)
                .to(delayExchange)
                .with(ROUTING_KEY);
    }
}

这个配置类定义了一个延迟消息队列（通过delay_exchange实现）和一个死信队列（当消息在延迟队列中等待超过指定时间后，会被重新发送到dead_letter_queue）。这里使用了Spring AMQP的QueueBuilder和BindingBuilder来简化配置。这个配置类可以作为Spring Boot应用的一部分，通过@Configuration注解被Spring容器自动加载。