maven依赖

<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>0.11.0.0</version>
</dependency>

不带回调函数的API

需要用到的类：
KafkaProducer：需要创建一个生产者对象，用来发送数据
ProducerConfig：获取所需的一系列配置参数
ProducerRecord：每条数据都要封装成一个ProducerRecord对象

package com.producer;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;
import java.util.Properties;
import java.util.concurrent.ExecutionException;
public class CustomProducer {
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        Properties props = new Properties();
        //kafka集群，broker-list
        props.put("bootstrap.servers", "zjj101:9092");
        props.put("acks", "all");
        //重试次数
        props.put("retries", 1);
        //批次大小
        props.put("batch.size", 16384);
        //等待时间
        props.put("linger.ms", 1);
        //RecordAccumulator缓冲区大小
        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<String, String> producer = new KafkaProducer<>(props);
        for (int i = 0; i < 100; i++) {
            //往topic为false发送数据
            producer.send(new ProducerRecord<String, String>("first", Integer.toString(i), Integer.toString(i)));
        }
        producer.close();
    }
}

带回调函数的API

回调函数会在producer收到ack时调用，为异步调用，该方法有两个参数，分别是RecordMetadata和Exception，如果Exception为null，说明消息发送成功，如果Exception不为null，说明消息发送失败。
注意：消息发送失败会自动重试，不需要我们在回调函数中手动重试。

因为是异步调用,Kafka发送的进度和接收回调的进度完全是不一致的,

package com.producer;
import org.apache.kafka.clients.producer.*;
import java.util.Properties;
import java.util.concurrent.ExecutionException;
public class CustomProducer2 {
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        Properties props = new Properties();
        props.put("bootstrap.servers", "zjj101:9092");//kafka集群，broker-list
        props.put("acks", "all");
        props.put("retries", 1);//重试次数
        props.put("batch.size", 16384);//批次大小
        props.put("linger.ms", 1);//等待时间
        props.put("buffer.memory", 33554432);//RecordAccumulator缓冲区大小
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        Producer<String, String> producer = new KafkaProducer<>(props);
        for (int i = 0; i < 100; i++) {
            producer.send(new ProducerRecord<String, String>("first", Integer.toString(i), Integer.toString(i)), new Callback() {
                //回调函数，该方法会在Producer收到ack时调用，为异步调用
                @Override
                public void onCompletion(RecordMetadata metadata, Exception exception) {
                    if (exception == null) {
                        System.out.println("success->" + metadata.offset());
                    } else {
                        exception.printStackTrace();
                    }
                }
            });
        }
        producer.close();
    }
}