Kafka+Log4j2日志

默认你已经安装配置了Zookeeper和Kafka。

为了目录清晰，我的Kafka配置文件的Zookeeper部分是：加上了节点用来存放Kafka信息

启动Zookeeper，然后启动Kafka。

Zookeeper的节点树：根目录下有专门的Kafka存放节点【以前没有配这个，结果Kafka的一大堆东西全部跑到根节点上了，很乱】

接下来是代码部分了。

依赖包：

Log4j2配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<Configuration monitorInterval="1800">

    <Filter type="ThresholdFilter" level="trace" />

    <Appenders>
        <Console name="console" target="SYSTEM_OUT">
            <!--控制台只输出level及以上级别的信息（onMatch），其他的直接拒绝（onMismatch） -->
            <ThresholdFilter level="trace" onMatch="ACCEPT"
                onMismatch="DENY" />
            <PatternLayout pattern="%d %-5p [%t] %C{2} (%F:%L) - %m%n" />
        </Console>

        <Kafka name="Kafka" topic="my-topic" syncSend="false">
            <PatternLayout pattern="%date %message" />
            <Property name="bootstrap.servers">192.168.127.129:9092,192.168.127.130:9092,192.168.127.131:9092</Property>
        </Kafka>
    </Appenders>
    <Loggers>
        <Root level="WARN">
            <!-- TRACE < DEBUG < INFO < WARN < ERROR < FATAL -->
            <AppenderRef ref="console" />
        </Root>
        <Logger name="kafkaLog" level="trace">
            <AppenderRef ref="Kafka" />
        </Logger>
    </Loggers>
</Configuration>

生产者：

package learn.kafka.log4j;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class SimpleProducer {

    private static Logger log = LogManager.getLogger("kafkaLog");
    
    public static void main(String[] args) {
        for (int i = 10; i < 20; i++) {
            log.info("Hello---" + i);
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
    
}

消费者：

package learn.kafka.log4j;

import java.util.Arrays;
import java.util.Properties;

import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;

public class SimpleConsumer {

    public static void main(String[] args) {
        Properties props = new Properties();
        props.put("bootstrap.servers", "192.168.127.129:9092,192.168.127.130:9092,192.168.127.131:9092");
        props.put("group.id", "testGroup");
        props.put("enable.auto.commit", "true");
        props.put("auto.commit.interval.ms", "1000");
        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);
        //订阅的topic，多个用逗号隔开
        consumer.subscribe(Arrays.asList("my-topic"));
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(100);
            for (ConsumerRecord<String, String> record : records)
                System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(), record.value());
        }
        //consumer.close();
    }
}

先运行消费者，让它监听等待。

在运行生产者，让它生产消息。

你会发现每隔一秒输出一行信息。信息在value后面。