消费者消费消息的基本实现
测试代码
package com.example.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 org.apache.kafka.common.serialization.StringDeserializer;
import java.time.Duration;
import java.util.Arrays;
import java.util.Properties;
public class MySimpleConsumer {
private final static String TOPIC_NAME = "test";
private final static String CONSUMER_GROUP_NAME = "testGroup";
public static void main(String[] args) {
Properties props = new Properties();
props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG,
"81.68.232.188:9092,81.68.232.188:9093,81.68.232.188:9094");
// 消费分组名
props.put(ConsumerConfig.GROUP_ID_CONFIG, CONSUMER_GROUP_NAME);
props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG,
StringDeserializer.class.getName());
props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG,
StringDeserializer.class.getName());
//1.创建⼀个消费者的客户端
KafkaConsumer< String, String > consumer = new KafkaConsumer < String,
String > (props);
//2. 消费者订阅主题列表
consumer.subscribe(Arrays.asList(TOPIC_NAME));
while (true) {
/*
* 3.poll() API 是拉取消息的⻓轮询
*/
ConsumerRecords< String, String > records =
consumer.poll(Duration.ofMillis(10000));
for (ConsumerRecord< String, String > record: records) {
//4.打印消息
System.out.printf("收到消息:partition = %d,offset = %d, key = %s, value = %s%n ", record.partition(),
record.offset(), record.key(), record.value());
}
}
}
}
配置日志打印
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<logger name="org.apache.kafka.clients" level="info" />
</configuration>
生产者发送消息
消费者默认消费最新消息