如何获取Kafka生产者消息计数

import org.apache.kafka.clients.producer.*;

public class KafkaProducerExample {
    private static int messageCount = 0;

    public static void main(String[] args) {
        // 配置Kafka生产者
        Properties props = new Properties();
        props.put("bootstrap.servers", "kafka-broker1:9092,kafka-broker2:9092");
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

        // 创建生产者实例
        Producer<String, String> producer = new KafkaProducer<>(props);

        // 发送消息
        for (int i = 0; i < 10; i++) {
            String message = "Message " + i;
            producer.send(new ProducerRecord<>("my-topic", message), new Callback() {
                @Override
                public void onCompletion(RecordMetadata metadata, Exception exception) {
                    if (exception == null) {
                        messageCount++; // 递增计数器
                        System.out.println("Message sent successfully");
                    } else {
                        System.out.println("Error sending message: " + exception.getMessage());
                    }
                }
            });
        }

        // 关闭生产者
        producer.close();

        // 输出消息计数
        System.out.println("Total messages sent: " + messageCount);
    }
}