kafka的API
第一步：导入kafka的开发jar包
<dependencies>
<!--
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>0.11.0.1</version>
</dependency>
-->
<!-- https://mvnrepository.com/artifact/org.apache.kafka/kafka-clients -->
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>1.0.0</version>
</dependency>
</dependencies>
Kafka生产者
@Test
public void kafkaProducer() throws Exception {
//1、准备配置文件
Properties props = new Properties();
props.put("bootstrap.servers", "hadoop-001:9092,hadoop-002:9092,hadoop-003:9092");
props.put("acks", "all");
props.put("retries", 0);
props.put("batch.size", 16384);
props.put("linger.ms", 1);
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");
//2、创建KafkaProducer
KafkaProducer<String, String> kafkaProducer = new KafkaProducer<String, String>(props);
for (int i=0;i<100;i++){
//3、发送数据
kafkaProducer.send(new ProducerRecord<String, String>("yun01","num"+i,"value"+i));
}
kafkaProducer.close();
}
Kafka消费者
@Test
public void kafkaConsum() throws Exception {
// 1、准备配置文件
Properties props = new Properties();
props.put("bootstrap.servers", "hadoop-001:9092,hadoop-002:9092,hadoop-003:9092");
props.put("group.id", "test");
props.put("enable.auto.commit", "true");
props.put("auto.commit.interval.ms", "1000");
props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
// 2、创建KafkaConsumer
KafkaConsumer<String, String> kafkaConsumer = new KafkaConsumer<String, String>(props);
// 3、订阅数据，这里的topic可以是多个
kafkaConsumer.subscribe(Arrays.asList("yun01"));
// 4、获取数据
while (true) {
ConsumerRecords<String, String> records = kafkaConsumer.poll(100);
for (ConsumerRecord<String, String> record : records) {
System.out.printf("topic = %s,offset = %d, key = %s, value = %s%n",record.topic(), record.offset(), record.key(), record.value());
}
}
}
kafka的自定义分区
第一种方式：直接指定分区
kafkaProducer.send(new ProducerRecord<String, String>("testpart",1,"0","value"+i));
第二种自定义分区
public class KafkaCustomPartitioner implements Partitioner {
@Override
public void configure(Map<String, ?> configs) {
}
@Override
public int partition(String topic, Object arg1, byte[] keyBytes, Object arg3, byte[] arg4, Cluster cluster) {
List<PartitionInfo> partitions = cluster.partitionsForTopic(topic);
int partitionNum = partitions.size();
Random random = new Random();
int partition = random.nextInt(partitionNum);
return partition;
}
@Override
public void close() {
}
}
主代码中添加配置
@Test
public void kafkaProducer() throws Exception {
//1、准备配置文件
Properties props = new Properties();
props.put("bootstrap.servers", "hadoop-001:9092,hadoop-002:9092,hadoop-003:9092");
props.put("acks", "all");
props.put("retries", 0);
props.put("batch.size", 16384);
props.put("linger.ms", 1);
props.put("buffer.memory", 33554432);
props.put("partitioner.class", "com.gec.kafkaclient.MyCustomerPartitons");
props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
//2、创建KafkaProducer
KafkaProducer<String, String> kafkaProducer = new KafkaProducer<String, String>(props);
for (int i=0;i<100;i++){
//3、发送数据
kafkaProducer.send(new ProducerRecord<String, String>("testpart","0","value"+i));
}
kafkaProducer.close();
}