java 45 lines · 6 steps

Manual RabbitMQ acks in a Spring listener

A Spring AMQP listener that explicitly acks, rejects, or requeues order messages based on how processing fails.

Explained by highlit

Spring Intermediate message-queue error-handling acknowledgement idempotency rabbitmq

1package com.example.orders.messaging;
2 
3import com.example.orders.dto.OrderEvent;
4import com.example.orders.service.OrderProcessingService;
5import com.rabbitmq.client.Channel;
6import org.slf4j.Logger;
7import org.slf4j.LoggerFactory;
8import org.springframework.amqp.rabbit.annotation.RabbitListener;
9import org.springframework.amqp.support.AmqpHeaders;
10import org.springframework.messaging.handler.annotation.Header;
11import org.springframework.messaging.handler.annotation.Payload;
12import org.springframework.stereotype.Component;
13 
14import java.io.IOException;
15 
16@Component
17public class OrderEventListener {
18 
19    private static final Logger log = LoggerFactory.getLogger(OrderEventListener.class);
20 
21    private final OrderProcessingService orderProcessingService;
22 
23    public OrderEventListener(OrderProcessingService orderProcessingService) {
24        this.orderProcessingService = orderProcessingService;
25    }
26 
27    @RabbitListener(queues = "orders.created", ackMode = "MANUAL")
28    public void onOrderCreated(
29            @Payload OrderEvent event,
30            Channel channel,
31            @Header(AmqpHeaders.DELIVERY_TAG) long deliveryTag,
32            @Header(name = AmqpHeaders.REDELIVERED, defaultValue = "false") boolean redelivered) throws IOException {
33 
34        try {
35            orderProcessingService.process(event);
36            channel.basicAck(deliveryTag, false);
37        } catch (IllegalStateException permanent) {
38            log.warn("Rejecting unprocessable order {}: {}", event.orderId(), permanent.getMessage());
39            channel.basicReject(deliveryTag, false);
40        } catch (Exception transientFailure) {
41            log.error("Failed to process order {} (redelivered={})", event.orderId(), redelivered, transientFailure);
42            channel.basicNack(deliveryTag, false, !redelivered);
43        }
44    }
45}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1Manual ack mode lets you distinguish permanent failures from transient ones instead of blindly requeuing everything.
2Rejecting with requeue=false hands poison messages to a dead-letter queue rather than looping forever.
3Tracking the redelivered flag prevents infinite retry loops by requeuing only on the first transient failure.

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