Kafka初試

二、安裝Kafka

1. 安裝Java
2. 安裝Zookeeper
   • 啓動命令： zkServer.sh start
   • 停止命令： zkServer.sh stop
3. 安裝Kafka
   • 啓動命令： kafka-server-start.sh config/server.properties
   • 啓動命令： kafka-server-stop.sh config/server.properties

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三、代碼實踐

添加Maven依賴

<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka-clients</artifactId>
    <version>2.0.0</version>
</dependency>

生產者客戶端代碼

public class ProducerFastStart {
    public static final String brokerList = "localhost:9092";
    public static final String topic = "topic-demo";
    public static void main(String[] args) {
        Properties properties = new Properties();
        properties.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        properties.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        properties.put("bootstrap.servers", brokerList);
        KafkaProducer<String, String> producer = new KafkaProducer<>(properties);
        ProducerRecord<String, String> record = new ProducerRecord<>(topic, "hello, Kafka!");
        try{
            producer.send(record);
        }catch (Exception e){
            e.printStackTrace();
        }
        producer.close();
    }
}

消費者客戶端代碼

public class ConsumerFastStart {
    public static final String brokerList = "localhost:9092";
    public static final String topic = "topic-demo";
    public static final String groupId = "group.demo";
    public static void main(String[] args) {
        Properties properties = new Properties();
        properties.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        properties.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        properties.put("bootstrap.servers", brokerList);
        properties.put("group.id", groupId);
        KafkaConsumer<String, String> consumer = new KafkaConsumer<>(properties);
        consumer.subscribe(Collections.singletonList(topic));
        while (true){
            ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(1000));
            for(ConsumerRecord<String, String> record : records){
                System.out.println(record.value());
            }
        }
    }
}