Kafka 简单Java示例

import java.util.Properties;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;

public class SimpleProducer {
   public static void main(String[] args) throws Exception{
		String topicName = "Hello-Kafka";
		Properties props = new Properties();
		// 如果使用IP地址连接需要在kafka配置文件service.properties
		// advertised.listeners=PLAINTEXT://YOURSELF-IP:9092
		props.put("bootstrap.servers", "localhost:9092");
		// Set acknowledgements for producer requests.      
		props.put("acks", "all");
		// If the request fails, the producer can automatically retry,
		props.put("retries", 0);
		//Specify buffer size in config
		props.put("batch.size", 16384);
		// Reduce the no of requests less than 0   
		props.put("linger.ms", 1);
		// The buffer.memory controls the total amount 
		// of memory available to the producer for buffering.   
		props.put("buffer.memory", 33554432);
		props.put("key.serializer", 
		"org.apache.kafka.common.serialization.StringSerializer");
		props.put("value.serializer", 
		"org.apache.kafka.common.serialization.StringSerializer");
		Producer producer = new KafkaProducer<>(props);
		for(int i = 0; i < 10; i++) {
			String key = Integer.toString(i);
			String value = Integer.toString(i);
			producer.send(new ProducerRecord<>(topicName, key, value));
		}
		System.out.println("Message sent successfully");
		producer.close();
   }
}

import java.util.Properties;
import java.util.Arrays;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.ConsumerRecord;

public class SimpleConsumer {
   public static void main(String[] args) throws Exception {
      String topicName = "Hello-Kafka";
      Properties props = new Properties();
      props.put("bootstrap.servers", "localhost:9092");
      props.put("group.id", "test");
      props.put("enable.auto.commit", "true");
      props.put("auto.commit.interval.ms", "1000");
      props.put("session.timeout.ms", "30000");
      props.put("key.deserializer", 
         "org.apache.kafka.common.serialization.StringDeserializer");
      props.put("value.deserializer", 
         "org.apache.kafka.common.serialization.StringDeserializer");
      KafkaConsumer consumer = new KafkaConsumer<>(props);
      // Kafka Consumer subscribes list of topics here.
      consumer.subscribe(Arrays.asList(topicName))
      //print the topic name
      System.out.println("Subscribed to topic: " + topicName);
      while (true) {
         ConsumerRecords records = consumer.poll(100);
         for (ConsumerRecord record : records)
         // print the offset,key and value for the consumer records.
         System.out.printf("offset = %d, key = %s, value = %sn", 
         record.offset(), record.key(), record.value());
      }
   }
}