Kafka自定义Consumer

代码实现

public class CustomConsumer {
    public static void main(String[] args) {
        Properties props = new Properties();
        // 定义kakfa 服务的地址，不需要将所有broker指定上
        props.put("bootstrap.servers", "hcmaster:9092");
        // 制定消费者组id
        props.put("group.id", "g1");
        // 是否自动确认offset
        props.put("enable.auto.commit", "true");
        // 自动确认offset的时间间隔
        props.put("auto.commit.interval.ms", "1000");
        // key的序列化类
        props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        // value的序列化类
        props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        // 定义consumer
        KafkaConsumer consumer = new KafkaConsumer(props);

        // 消费者订阅的topic, 可同时订阅多个
        consumer.subscribe(Arrays.asList("first","second"));

        while (true) {
            // 读取数据，读取超时时间为100ms
            ConsumerRecords records = consumer.poll(Duration.ofMillis(100));
            for (ConsumerRecord record : records) {
                System.out.printf("topic = %s , partition = %s , offset = %d, key = %s, value = %s%n",record.topic(), record.partition(), record.offset(), record.key(), record.value());
            }
        }
    }
}

测试

在终端分别启动fist和second两个Producer 发送数据顺序：

1. first发送aa、bb
2. second发送11、22
3. first发送33
4. second发送cc

Intellij控制台输出结果：