kafka producer demo

package com.producer;


import com.alibaba.fastjson.JSON;
import com.baturu.message.Message;
import com.dto.OrderDetailTimeCostCompleteMessageDTO;
import com.dto.TimeCostCompleteMessageDTO;
import com.fasterxml.jackson.databind.ObjectMapper;


import java.util.*;


import com.google.common.collect.Lists;
import lombok.extern.slf4j.Slf4j;
import org.apache.kafka.clients.producer.*;
import org.apache.kafka.clients.producer.Producer;


/**
* Date: 2019-05-20 00:04
*/
@Slf4j
public class ProducerDemo {

    // 以下两个属性也可以作为send方法的参数，更灵活些
    private static Properties properties = getConf();
    private static String jsonMsg =getJsonMsg();

    static void send() {
        Producer<String, String> producer = null;
        try {
            producer = new KafkaProducer<>(properties);
            
            ProducerRecord<String, String> record = new ProducerRecord<>("TOPIC", jsonMsg);
            producer.send(record, (metadata, e)-> {
                if (metadata != null) {
                    log.info("sent record(key={} value={}) meta(partition={}, offset={})",
                            record.key(), record.value(), metadata.partition(),
                            metadata.offset());
                } else {
                    log.error(e.getMessage(), e);
                }
            });
        } catch (Exception e) {
            log.error(e.getMessage(), e);
        }finally {
            // 一定要关闭资源，否则消息发送不成功
            try {
                if (producer != null) {
                    producer.close();
                }
            } catch (Exception e) {
                log.error(e.getMessage(), e);
            }
        }
    }


    private static Properties getConf() {
        Properties properties = new Properties();
        // ProducerConfig 类定义了生产者相关的配置
        // 指定kafka 连接的集群
        properties.put("bootstrap.servers", "xxx");
        // ack应答级别
        properties.put("acks", "all");
        // 重试次数
        properties.put("retries", 0);
        // 单次发送批次的大小
        properties.put("batch.size", 16384);
        // 批次大小不足的情况等待发送时间
        properties.put("linger.ms", 1);
        // RecordAccumulator 缓冲区大小
        properties.put("buffer.memory", 33554432);

        // key - value序列化
        properties.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        properties.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        return properties;
    }



    private static String getJsonMsg() {
          TimeCostCompleteMessageDTO messageDTO = TimeCostCompleteMessageDTO.builder()
                    .orderId(xxxxx)
                    .build();
            Message message = new Message();
            message.setContent(messageDTO);
            retrun JSON.toJSONString(message);
    }
}