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;
9 import org.springframework.scheduling.annotation.Async;
11 import java.time.Duration;
12 import java.util.Arrays;
16 @RequiredArgsConstructor
17 public class SimpleConsumer
19 private final String id;
20 private final String topic;
21 private final Consumer<String, String> consumer;
23 private volatile boolean running = false;
24 private long consumed = 0;
32 log.info("{} - Subscribing to topic test", id);
33 consumer.subscribe(Arrays.asList(topic));
38 ConsumerRecords<String, String> records =
39 consumer.poll(Duration.ofSeconds(1));
41 log.info("{} - Received {} messages", id, records.count());
42 for (ConsumerRecord<String, String> record : records)
46 "{} - {}: {}/{} - {}={}",
57 catch(WakeupException e)
59 log.info("{} - Consumer was signaled to finish its work", id);
63 log.error("{} - Unexpected error: {}, unsubscribing!", id, e.toString());
64 consumer.unsubscribe();
69 log.info("{} - Closing the KafkaConsumer", id);
71 log.info("{}: Consumed {} messages in total, exiting!", id, consumed);
75 public boolean isRunning()