如何在kafka消费者中按内容设置主题？

import org.apache.kafka.clients.consumer.*;
import org.apache.kafka.common.TopicPartition;

import java.util.*;

public class KafkaConsumerExample {
    public static void main(String[] args) {
        Properties props = new Properties();
        props.put("bootstrap.servers", "localhost:9092");
        props.put("group.id", "test-group");
        props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
        consumer.subscribe(Arrays.asList("topic1", "topic2"));

        try {
            while (true) {
                ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(100));
                for (ConsumerRecord<String, String> record : records) {
                    // 根据消息内容进行过滤
                    if (record.value().contains("keyword")) {
                        // 处理满足条件的消息
                        System.out.println("Received message: " + record.value());
                    }
                }
            }
        } finally {
            consumer.close();
        }
    }
}