juplo.de Git - demos/kafka/training/blob - src/main/java/de/juplo/kafka/SimpleProducer.java

   1 package de.juplo.kafka;
   2
   3 import lombok.extern.slf4j.Slf4j;
   4 import org.apache.kafka.clients.producer.Producer;
   5 import org.apache.kafka.clients.producer.KafkaProducer;
   6 import org.apache.kafka.clients.producer.ProducerRecord;
   7 import org.apache.kafka.common.serialization.StringSerializer;
   8
   9 import java.util.Properties;
  10
  11
  12 @Slf4j
  13 public class SimpleProducer
  14 {
  15   private final String id;
  16   private final String topic;
  17   private final Producer<String, String> producer;
  18
  19   private long produced = 0;
  20
  21   public SimpleProducer(String clientId, String topic)
  22   {
  23     // tag::create[]
  24     Properties props = new Properties();
  25     props.put("bootstrap.servers", "localhost:9092");
  26     props.put("key.serializer", StringSerializer.class.getName());
  27     props.put("value.serializer", StringSerializer.class.getName());
  28
  29     Producer<String, String> producer = new KafkaProducer<>(props);
  30     // end::create[]
  31
  32     this.id = clientId;
  33     this.topic = topic;
  34     this.producer = producer;
  35   }
  36
  37   public void run()
  38   {
  39     long i = 0;
  40
  41     try
  42     {
  43       for (; i < 100 ; i++)
  44       {
  45         send(Long.toString(i%10), Long.toString(i));
  46       }
  47
  48       log.info("{} - Done", id);
  49     }
  50     finally
  51     {
  52       log.info("{}: Closing the KafkaProducer", id);
  53       producer.close();
  54       log.info("{}: Produced {} messages in total, exiting!", id, produced);
  55     }
  56   }
  57
  58   void send(String key, String value)
  59   {
  60     final long time = System.currentTimeMillis();
  61
  62     final ProducerRecord<String, String> record = new ProducerRecord<>(
  63         topic,  // Topic
  64         key,    // Key
  65         value   // Value
  66     );
  67
  68     producer.send(record, (metadata, e) ->
  69     {
  70       long now = System.currentTimeMillis();
  71       if (e == null)
  72       {
  73         // HANDLE SUCCESS
  74         produced++;
  75         log.debug(
  76             "{} - Sent key={} message={} partition={}/{} timestamp={} latency={}ms",
  77             id,
  78             record.key(),
  79             record.value(),
  80             metadata.partition(),
  81             metadata.offset(),
  82             metadata.timestamp(),
  83             now - time
  84         );
  85       }
  86       else
  87       {
  88         // HANDLE ERROR
  89         log.error(
  90             "{} - ERROR key={} timestamp={} latency={}ms: {}",
  91             id,
  92             record.key(),
  93             metadata == null ? -1 : metadata.timestamp(),
  94             now - time,
  95             e.toString()
  96         );
  97       }
  98     });
  99
 100     long now = System.currentTimeMillis();
 101     log.trace(
 102         "{} - Queued #{} key={} latency={}ms",
 103         id,
 104         value,
 105         record.key(),
 106         now - time
 107     );
 108   }
 109
 110
 111   public static void main(String[] args) throws Exception
 112   {
 113     SimpleProducer producer = new SimpleProducer("P", "test");
 114     producer.run();
 115   }
 116 }