Kafka总结

一、安装&启动

在Kafka官网下载安装包kafka_2.11-1.0.0.tgz

## 解压
tar zxvf kafka_2.11-1.0.0.tgz

## 启动内置的zookeeper
.bin/zookeeper-server-start.sh ../config/zookeeper.properties

## 启动kafka
./bin/kafka-server-start.sh ../config/server.properties

二、终端命令

创建主题

./kafka-topics.sh --create --zookeeper localhost:2181 --topic test --partitions 1 --replication-factor 1

查看主题

./kafka-topics.sh --describe --zookeeper localhost:2181 --topic test

生产消息

./kafka-console-producer.sh --broker-list localhost:9092 --topic test

消费消息

./kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic test --from-beginning

三、客户端连接

1、引入依赖

        <!-- https://mvnrepository.com/artifact/org.apache.kafka/kafka-clients -->
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>1.0.0</version>
        </dependency>

2、生产

public class KafkaProducerDemo {

    public static void main(String[] args) {

        Properties props = new Properties();
        props.put("bootstrap.servers", "localhost:9092");
        props.put("acks", "-1");
        props.put("retries", 3);
        props.put("batch.size", 16384);
        props.put("linger.ms", 10);
        props.put("buffer.memory", 33554432);
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("max.blocks.ms", "3000");

        Producer<String, String> producer = new KafkaProducer<String, String>(props);

        for (int i = 0; i < 100; i++) {
            try {
                producer.send(new ProducerRecord<String, String>("testfzj", Integer.toString(i), Integer.toString(i))).get();
            } catch (InterruptedException e) {
                e.printStackTrace();
            } catch (ExecutionException e) {
                e.printStackTrace();
            }

        }
        producer.close();

        System.out.println("发送完成");
    }

}

3、消费

public class KafkaConsumerDemo {

    public static void main(String[] args) {
        String topicName = "testfzj";
        String gorupId = "test-group";

        Properties props = new Properties();
        props.put("bootstrap.servers", "localhost:9092");
        props.put("group.id", gorupId);
        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);
        consumer.subscribe(Arrays.asList(topicName));
        try {
            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());
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            consumer.close();
        }
    }

}

四、常见问题

org.apache.kafka.common.errors.TimeoutException

使用Java客户端生产消息，出现此异常提示。

原因：外网访问，需要修改server.properties参数，将IP地址改为公网的IP地址，然后重启服务

advertised.listeners=PLAINTEXT://59.11.11.11:9092

可参考 https://www.cnblogs.com/snifferhu/p/5102629.html

来源：https://www.cnblogs.com/fonxian/p/11837191.html