1 package de.juplo.kafka;
3 import lombok.RequiredArgsConstructor;
4 import lombok.extern.slf4j.Slf4j;
5 import org.apache.kafka.clients.consumer.Consumer;
6 import org.apache.kafka.clients.consumer.ConsumerRecord;
7 import org.apache.kafka.clients.consumer.ConsumerRecords;
8 import org.apache.kafka.common.errors.WakeupException;
10 import java.time.Duration;
11 import java.util.Arrays;
15 @RequiredArgsConstructor
16 public class SimpleConsumer implements Runnable
18 private final String id;
19 private final String topic;
20 private final Consumer<String, String> consumer;
22 private long consumed = 0;
30 log.info("{} - Subscribing to topic test", id);
31 consumer.subscribe(Arrays.asList(topic));
35 ConsumerRecords<String, String> records =
36 consumer.poll(Duration.ofSeconds(1));
38 log.info("{} - Received {} messages", id, records.count());
39 for (ConsumerRecord<String, String> record : records)
43 "{} - {}: {}/{} - {}={}",
54 catch(WakeupException e)
56 log.info("{} - Consumer was signaled to finish its work", id);
60 log.error("{} - Unexpected error: {}, unsubscribing!", id, e.toString());
61 consumer.unsubscribe();
65 log.info("{} - Closing the KafkaConsumer", id);
67 log.info("{}: Consumed {} messages in total, exiting!", id, consumed);