- this.executor = executor;
- this.bootstrapServer = bootstrapServer;
- this.groupId = groupId;
- this.id = clientId;
- this.topic = topic;
- }
-
- @Override
- public void run()
- {
- Properties props = new Properties();
- props.put("bootstrap.servers", bootstrapServer);
- props.put("group.id", groupId);
- props.put("client.id", id);
- props.put("auto.offset.reset", "earliest");
- props.put("key.deserializer", StringDeserializer.class.getName());
- props.put("value.deserializer", StringDeserializer.class.getName());
-
- this.consumer = new KafkaConsumer<>(props);
-
- try
- {
- log.info("{} - Subscribing to topic {}", id, topic);
- consumer.subscribe(Arrays.asList(topic));
-
- while (true)
- {
- ConsumerRecords<String, String> records =
- consumer.poll(Duration.ofSeconds(1));
-
- // Do something with the data...
- log.info("{} - Received {} messages", id, records.count());
- for (ConsumerRecord<String, String> record : records)
- {
- consumed++;
- log.info(
- "{} - {}: {}/{} - {}={}",
- id,
- record.offset(),
- record.topic(),
- record.partition(),
- record.key(),
- record.value()
- );
- }
- }
- }
- catch(WakeupException e)
- {
- log.info("{} - RIIING!", id);
- }
- catch(Exception e)
- {
- log.error("{} - Unexpected error: {}", id, e.toString());
- running.set(false); // Mark the instance as not running
- }
- finally
- {
- log.info("{} - Closing the KafkaConsumer", id);
- consumer.close();
- log.info("{} - Consumer-Thread exiting", id);
- }
- }
-
-
- public synchronized void start()
- {
- boolean stateChanged = running.compareAndSet(false, true);
- if (!stateChanged)
- throw new RuntimeException("Consumer instance " + id + " is already running!");
-
- log.info("{} - Starting - consumed {} messages before", id, consumed);
- future = executor.submit(this);
- }
-
- public synchronized void stop() throws ExecutionException, InterruptedException
- {
- boolean stateChanged = running.compareAndSet(true, false);
- if (!stateChanged)
- throw new RuntimeException("Consumer instance " + id + " is not running!");
-
- log.info("{} - Stopping", id);
- consumer.wakeup();
- future.get();
- log.info("{} - Stopped - consumed {} messages so far", id, consumed);
- }
-
- @PreDestroy
- public void destroy() throws ExecutionException, InterruptedException
- {
- log.info("{} - Destroy!", id);
- try
- {
- stop();
- }
- catch (IllegalStateException e)
- {
- log.info("{} - Was already stopped", id);
- }
- finally