kafka-java统计kafka消息总数

以下是使用Java统计Kafka消息总数的示例代码：

import java.util.Properties;
import org.apache.kafka.clients.consumer.ConsumerConfig;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.common.TopicPartition;

public class KafkaMessageCounter {
    public static void main(String[] args) {
        String topicName = "your_topic_name";
        String bootstrapServers = "localhost:9092"; // Kafka集群地址
        String groupId = "test_group"; // 消费者组ID

        Properties props = new Properties();
        props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapServers);
        props.put(ConsumerConfig.GROUP_ID_CONFIG, groupId);
        props.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, "false");
        props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
        props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
        TopicPartition partition = new TopicPartition(topicName, 0);
        consumer.assign(Arrays.asList(partition));
        consumer.seekToBeginning(Arrays.asList(partition));

        long messageCount = 0;
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(100);
            if (records.isEmpty()) {
                break;
            }
            for (ConsumerRecord<String, String> record : records) {
                messageCount++;
            }
        }

        System.out.println("Total message count: " + messageCount);
        consumer.close();
    }
}

这段代码使用Kafka消费者API来消费指定topic的所有消息，并统计消息总数。需要注意的是，这里使用了手动提交offset的方式，以确保消息不会被重复消费。