java - 如何在 Java 中从特定偏移量开始消费来自 Kafka 的消息

Question

从最早的开始阅读:

props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");

阅读最新内容:

props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "latest");

但是如果我想开始，例如:从第 18 次提交开始，我应该使用哪一行？

Answer 1

您可以使用seek()为了强制消费者从特定的偏移量开始消费:

public void seek(TopicPartition partition, long offset)

Overrides the fetch offsets that the consumer will use on the next poll(timeout). If this API is invoked for the same partition more than once, the latest offset will be used on the next poll(). Note that you may lose data if this API is arbitrarily used in the middle of consumption, to reset the fetch offsets

---

例如，假设您想从偏移量 18 开始:

TopicPartition topicPartition = new TopicPartition("myTopic", 0);
Long startOffset = 18L;
    
List<TopicPartition> topics = Arrays.asList(topicPartition);
consumer.assign(topics);
consumer.seek(topicPartition, startOffset);

// Then consume messages as normal..