Kafka: 生产者发送消息的三种方式

1.同步
public class ProducerMain2 {

public static void main(String[] args) throws Exception {
  // 配置信息
  Properties props = new Properties();
  props.put("bootstrap.servers", "localhost:9092");
  // 设置数据key的序列化处理类
  props.put("key.serializer",
      "org.apache.kafka.common.serialization.StringSerializer");
  // 设置数据value的序列化处理类
  props.put("value.serializer",
      "org.apache.kafka.common.serialization.StringSerializer");
  // 创建生产者实例
  Producer<String, String> producer = new KafkaProducer<>(props); 
  // 创建一条新的记录，第一个参数为Topic名称
  ProducerRecord record = new ProducerRecord<String, String>("test", "currenttime","now is :"+ new Date().toString());
  // 发送记录
  Future<RecordMetadata> send=producer.send(record);
  RecordMetadata recordMetadata=send.get();
  System.out.println(recordMetadata);
  producer.close();
}

}
2异步：发送并忘记
package org.crazyit.cloud;

import java.util.Date;
import java.util.Properties;

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.common.serialization.StringSerializer;

/**

• 生产者
• @author 杨恩雄
• 
  

*/
public class ProducerMain {

public static void main(String[] args) throws Exception {
  // 配置信息
  Properties props = new Properties();
  props.put("bootstrap.servers", "localhost:9092");
  // 设置数据key的序列化处理类
  props.put("key.serializer",
      "org.apache.kafka.common.serialization.StringSerializer");
  // 设置数据value的序列化处理类
  props.put("value.serializer",
      "org.apache.kafka.common.serialization.StringSerializer");
  // 创建生产者实例
  Producer<String, String> producer = new KafkaProducer<>(props); 
  // 创建一条新的记录，第一个参数为Topic名称
  ProducerRecord record = new ProducerRecord<String, String>("test", "currenttime","now is :"+ new Date().toString());
  // 发送记录
  producer.send(record);
  producer.close();
}

}

3.异步回调
package org.crazyit.cloud;

import java.util.Date;
import java.util.Properties;
import java.util.concurrent.Future;

import org.apache.kafka.clients.producer.Callback;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.clients.producer.RecordMetadata;
import org.apache.kafka.common.serialization.StringSerializer;

/**

• 生产者
• @author 杨恩雄
• 
  

*/
public class ProducerMain3 {

public static void main(String[] args) throws Exception {
  // 配置信息
  Properties props = new Properties();
  props.put("bootstrap.servers", "localhost:9092");
  // 设置数据key的序列化处理类
  props.put("key.serializer",
      "org.apache.kafka.common.serialization.StringSerializer");
  // 设置数据value的序列化处理类
  props.put("value.serializer",
      "org.apache.kafka.common.serialization.StringSerializer");
  // 创建生产者实例
  Producer<String, String> producer = new KafkaProducer<>(props); 
  // 创建一条新的记录，第一个参数为Topic名称
  ProducerRecord record = new ProducerRecord<String, String>("test", "currenttime","now is :"+ new Date().toString());
  // 发送记录
  producer.send(record,new Callback()
      {

        @Override
        public void onCompletion(RecordMetadata metadata, Exception exception) {
          System.out.println("sent succesfully."+metadata);
          
        }
    
      });
  
  producer.close();
}

}