X-Git-Url: https://juplo.de/gitweb/?a=blobdiff_plain;f=src%2Fmain%2Fjava%2Fde%2Fjuplo%2Fkafka%2FSimpleConsumer.java;fp=src%2Fmain%2Fjava%2Fde%2Fjuplo%2Fkafka%2FSimpleConsumer.java;h=0000000000000000000000000000000000000000;hb=107010572c028dcacf7115b6f90e6afc63be00f8;hp=e4d969748e896ff18863cd465b6e8ab9ee91c2be;hpb=e6f1c395d5a14907b4a5da259bef615b476d372a;p=demos%2Fkafka%2Ftraining diff --git a/src/main/java/de/juplo/kafka/SimpleConsumer.java b/src/main/java/de/juplo/kafka/SimpleConsumer.java deleted file mode 100644 index e4d9697..0000000 --- a/src/main/java/de/juplo/kafka/SimpleConsumer.java +++ /dev/null @@ -1,131 +0,0 @@ -package de.juplo.kafka; - -import lombok.extern.slf4j.Slf4j; -import org.apache.kafka.clients.consumer.ConsumerRecord; -import org.apache.kafka.clients.consumer.ConsumerRecords; -import org.apache.kafka.clients.consumer.KafkaConsumer; -import org.apache.kafka.common.errors.WakeupException; -import org.apache.kafka.common.serialization.StringDeserializer; - -import java.time.Duration; -import java.util.Arrays; -import java.util.Properties; -import java.util.concurrent.locks.Condition; -import java.util.concurrent.locks.Lock; -import java.util.concurrent.locks.ReentrantLock; - - -@Slf4j -public class SimpleConsumer -{ - private long consumed = 0; - private KafkaConsumer consumer; - private Lock lock = new ReentrantLock(); - private Condition stopped = lock.newCondition(); - - - public SimpleConsumer() - { - // tag::create[] - Properties props = new Properties(); - props.put("bootstrap.servers", ":9092"); - props.put("group.id", "my-consumer"); // << Used for Offset-Commits - // end::create[] - props.put("auto.offset.reset", "earliest"); - // tag::create[] - props.put("key.deserializer", StringDeserializer.class.getName()); - props.put("value.deserializer", StringDeserializer.class.getName()); - - KafkaConsumer consumer = new KafkaConsumer<>(props); - // end::create[] - this.consumer = consumer; - } - - - public void run() - { - String id = "C"; - - try - { - log.info("{} - Subscribing to topic test", id); - consumer.subscribe(Arrays.asList("test")); - - // tag::loop[] - while (true) - { - ConsumerRecords records = - consumer.poll(Duration.ofSeconds(1)); - - // Do something with the data... - // end::loop[] - log.info("{} - Received {} messages", id, records.count()); - for (ConsumerRecord record : records) - { - consumed++; - log.info( - "{} - {}: {}/{} - {}={}", - id, - record.offset(), - record.topic(), - record.partition(), - record.key(), - record.value() - ); - } - // tag::loop[] - } - // end::loop[] - } - catch(WakeupException e) - { - log.info("{} - RIIING!", id); - } - catch(Exception e) - { - log.error("{} - Unexpected error: {}", id, e.toString()); - } - finally - { - this.lock.lock(); - try - { - log.info("{} - Closing the KafkaConsumer", id); - consumer.close(); - log.info("C - DONE!"); - stopped.signal(); - } - finally - { - this.lock.unlock(); - log.info("{}: Consumed {} messages in total, exiting!", id, consumed); - } - } - } - - - public static void main(String[] args) throws Exception - { - SimpleConsumer instance = new SimpleConsumer(); - - Runtime.getRuntime().addShutdownHook(new Thread(() -> - { - instance.lock.lock(); - try - { - instance.consumer.wakeup(); - instance.stopped.await(); - } - catch (InterruptedException e) - { - log.warn("Interrrupted while waiting for the consumer to stop!", e); - } - finally - { - instance.lock.unlock(); - } - })); - - instance.run(); - } -}