一、依赖

    <repositories>
        <repository>
            <id>cloudera</id>
            <url>https://repository.cloudera.com/artifactory/cloudera-repos/</url>
        </repository>
    </repositories>

    <properties>
    <kafka-version>2.1.0-cdh6.2.0</kafka-version>
    </properties>

    <dependencies>
        <!--kafka依赖-->
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>connect-api</artifactId>
            <version>${kafka-version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka_2.12</artifactId>
            <version>${kafka-version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>${kafka-version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-streams</artifactId>
            <version>${kafka-version}</version>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter</artifactId>
            <version>RELEASE</version>
            <scope>compile</scope>
        </dependency>
    </dependencies>

二、代码如下

package Demo;

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.TopicPartition;

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

public class kafkaDemo1 {
    public static void main(String[] args) {
        String topicName = "datapartition";

        //1.配置属性值
        Properties properties = new Properties();
        //kafka是服务器地址
        properties.put("bootstrap.servers", "hdp1:9092");
        //定义消费者组
        properties.put("group.id", "gmall");
        //自动提交（offset）
        properties.put("enable.auto.commit", "true");
        //自动处理的间隔时间1秒
        properties.put("auto.commit.interval.ms", "1000");
        //key和values的持久化设置
        properties.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        properties.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        //2.创建消费者
        KafkaConsumer<String, String> kafkaConsumer = new KafkaConsumer<String, String>(properties);
        //3.消费topic(可以有多个topic)
        kafkaConsumer.assign(Arrays.asList(new TopicPartition(topicName,0)));
        kafkaConsumer.seekToBeginning(Arrays.asList(new TopicPartition(topicName,0)));
        //4.执行消费的操作
        while (true) {
            //100ms消费一次
            //kafkaConsumer.poll(100)读出来，读到records
            ConsumerRecords<String, String> records = kafkaConsumer.poll(100);
            for (ConsumerRecord<String, String> record : records) {
                System.out.println("-----------------");
                //打印偏移量，key，value
                System.out.printf("offset = %d, key = %s, value = %s\n", record.offset(), record.key(), record.value());
                System.out.println();
            }
        }
    }
}

三、部分打印结果