KafkaTest3.java

package com.example.demo;

import static org.junit.Assert.assertTrue;

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import org.apache.kafka.clients.consumer.ConsumerConfig;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.apache.kafka.common.serialization.IntegerDeserializer;
import org.apache.kafka.common.serialization.IntegerSerializer;
import org.apache.kafka.common.serialization.StringDeserializer;
import org.apache.kafka.common.serialization.StringSerializer;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.kafka.annotation.EnableKafka;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.kafka.config.ConcurrentKafkaListenerContainerFactory;
import org.springframework.kafka.core.ConsumerFactory;
import org.springframework.kafka.core.DefaultKafkaConsumerFactory;
import org.springframework.kafka.core.DefaultKafkaProducerFactory;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.kafka.core.ProducerFactory;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
public class KafkaTest3 {

  @Autowired
  private Listener listener;

  @Autowired
  private KafkaTemplate<Integer, String> template;

  @Test
  public void testSimple() throws Exception {
    template.send("my-topic", Integer.valueOf(1), "foo");
    template.flush();
    assertTrue(this.listener.latch1.await(10, TimeUnit.SECONDS));
  }

  @Configuration
  @EnableKafka
  public static class Config {

    @Bean
    ConcurrentKafkaListenerContainerFactory<Integer, String> kafkaListenerContainerFactory() {
      ConcurrentKafkaListenerContainerFactory<Integer, String> factory = new ConcurrentKafkaListenerContainerFactory<>();
      factory.setConsumerFactory(consumerFactory());
      return factory;
    }

    @Bean
    public ConsumerFactory<Integer, String> consumerFactory() {
      return new DefaultKafkaConsumerFactory<>(consumerConfigs());
    }

    @Bean
    public Map<String, Object> consumerConfigs() {
      Map<String, Object> props = new HashMap<>();
      props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
      props.put(ConsumerConfig.GROUP_ID_CONFIG, "group1");
      props.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, true);
      props.put(ConsumerConfig.AUTO_COMMIT_INTERVAL_MS_CONFIG, "100");
      props.put(ConsumerConfig.SESSION_TIMEOUT_MS_CONFIG, "15000");
      props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, IntegerDeserializer.class);
      props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
      return props;
    }

    @Bean
    public Listener listener() {
      return new Listener();
    }

    @Bean
    public ProducerFactory<Integer, String> producerFactory() {
      return new DefaultKafkaProducerFactory<>(producerConfigs());
    }

    @Bean
    public Map<String, Object> producerConfigs() {
      Map<String, Object> props = new HashMap<>();
      props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
      props.put(ProducerConfig.RETRIES_CONFIG, 0);
      props.put(ProducerConfig.BATCH_SIZE_CONFIG, 16384);
      props.put(ProducerConfig.LINGER_MS_CONFIG, 1);
      props.put(ProducerConfig.BUFFER_MEMORY_CONFIG, 33554432);
      props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, IntegerSerializer.class);
      props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
      return props;
    }

    @Bean
    public KafkaTemplate<Integer, String> kafkaTemplate() {
      return new KafkaTemplate<Integer, String>(producerFactory());
    }

  }

  public static class Listener {

    private final CountDownLatch latch1 = new CountDownLatch(1);

    @KafkaListener(id = "foo", topics = "my-topic")
    public void listen1(String foo) {
      this.latch1.countDown();
    }

  }

}