在我的代码中,消费者订阅现有主题,但没有收到来自主题的消息请帮助我,它等待消息,而在kafka控制台消费者消息收到正确
package kafka;
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 java.util.Arrays;
import java.util.Properties;
public class SimpleConsumer {
public static void main(String[] args) throws Exception {
//Kafka consumer configuration settings
String topicName = "test12";
Properties props = new Properties();
props.put("bootstrap.servers", "localhost:9092");
props.put("group.id", "test");
props.put("enable.auto.commit", "true");
props.put("auto.commit.interval.ms", "1000");
props.put("session.timeout.ms", "30000");
props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
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
<String, String>(props);
//Kafka Consumer subscribes list of topics here.
consumer.subscribe(Arrays.asList(topicName));
//print the topic name
System.out.println("Subscribed to topic " + topicName);
int i = 0;
while (true) {
ConsumerRecords<String, String> records = consumer.poll(1000);
for (ConsumerRecord<String, String> record : records)
// print the offset,key and value for the consumer records.
System.out.printf("offset = %d, key = %s, value = %s\n",
record.offset(), record.key(), record.value());
}
}
}
1 回答
可能是偏移位于最新位置的情况 . 你可以尝试从头开始 .