kafka学习(1)linux下的安装和启动，以及Java示例代码

1. 安装

1.1 下载kafka并解压

wget http://mirror.bit.edu.cn/apache/kafka/0.11.0.0/kafka_2.11-0.11.0.0.tgz 
tar -zxvf kafka_2.11-0.11.0.0.tgz

1.2 修改配置

(1)配置zookeeper地址

vim /data/kafka_2.11-0.11.0.0/config/server.properties

zookeeper.connect=localhost:2181,localhost:2182,localhost:2183

(2)配置内存

vim /data/kafka_2.11-0.11.0.0/bin/kafka-server-start.sh

if [ "x$KAFKA_HEAP_OPTS" = "x" ]; then
export KAFKA_HEAP_OPTS="-Xmx256m -Xms256m"
fi

(3)敲黑板！修改对外的IP地址，否则kafka在别的机器上无法发布和订阅

[root@iZ2zei0nwllapkwklisoncZ kafka_2.11-0.11.0.0]# vim config/server.properties

advertised.listeners=PLAINTEXT://123.56.13.70:9092

1.3 启动

sh /data/kafka_2.11-0.11.0.0/bin/kafka-server-start.sh /data/kafka_2.11-0.11.0.0/config/server.properties

2. 发送和订阅消息

2.1 创建主题

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

2.2 查看主题

[root@iZ2zei0nwllapkwklisoncZ kafka_2.11-0.11.0.0]# bin/kafka-topics.sh  --list --zookeeper localhost:2181
test

2.3 发送消息produce

[root@iZ2zei0nwllapkwklisoncZ kafka_2.11-0.11.0.0]# bin/kafka-console-producer.sh --broker-list localhost:9092 --topic test
>我是高天悦
>

2.4 接收消息consume

[root@iZ2zei0nwllapkwklisoncZ kafka_2.11-0.11.0.0]# bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic test --from-beginning
this is a msg
this is another msg
你好

3. Java API 代码

3.1 生产者

public static String testProduce() {
Properties props = new Properties();
props.put("bootstrap.servers", KafkaConstants.BROKER_LIST);
props.put("acks", "all");
props.put("retries", 0);
props.put("batch.size", 16384);
props.put("linger.ms", 1);
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");

Producer<String, String> producer = new KafkaProducer<>(props);
for (int i = 0; i < 100; i++)
producer.send(
new ProducerRecord<String, String>("test", Integer.toString(i), Integer.toString(i)));

producer.close();
return "ok";
}

3.2 消费者

public static Object testConsume() {
Properties props = new Properties();
props.put("bootstrap.servers", "123.56.13.70:9092");
props.put("group.id", "d2");
props.put("enable.auto.commit", "false");
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");
props.put("session.timeout.ms", "30000");
KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);
//      consumer.subscribe(Arrays.asList("foo", "bar", "test"));
consumer.subscribe(Arrays.asList("test"));
long timeout = 10000;
while (true) {
ConsumerRecords<String, String> records = consumer.poll(timeout);
for (ConsumerRecord<String, String> record : records)
System.out.printf("offset = %d, key = %s, value = %s%n", record.offset(), record.key(),
record.value());
}
}

在控制台和Eclipse console同时看到生产和消费之间的通讯，bingo！

tips: kafka的持久化在/tmp/kafka-logs下

[root@iZ2zei0nwllapkwklisoncZ kafka-logs]# pwd

/tmp/kafka-logs

[root@iZ2zei0nwllapkwklisoncZ kafka-logs]# ll

total 232

drwxr-xr-x 2 root root 4096 Oct 15 19:07 baotest-0

drwxr-xr-x 2 root root 4096 Oct 15 19:07 bar-0

-rw-r–r– 1 root root 0 Oct 14 21:32 cleaner-offset-checkpoint

drwxr-xr-x 2 root root 4096 Oct 15 19:23 __consumer_offsets-0

drwxr-xr-x 2 root root 4096 Oct 15 19:07 __consumer_offsets-1

….

drwxr-xr-x 2 root root 4096 Oct 15 19:07 __consumer_offsets-5

drwxr-xr-x 2 root root 4096 Oct 15 19:07 __consumer_offsets-6

drwxr-xr-x 2 root root 4096 Oct 15 19:07 __consumer_offsets-7

drwxr-xr-x 2 root root 4096 Oct 15 19:07 __consumer_offsets-8

drwxr-xr-x 2 root root 4096 Oct 15 19:07 __consumer_offsets-9

drwxr-xr-x 2 root root 4096 Oct 15 19:07 foo-0

-rw-r–r– 1 root root 4 Oct 15 20:47 log-start-offset-checkpoint

-rw-r–r– 1 root root 54 Oct 14 21:33 meta.properties

-rw-r–r– 1 root root 1244 Oct 15 20:47 recovery-point-offset-checkpoint

-rw-r–r– 1 root root 1248 Oct 15 20:48 replication-offset-checkpoint

drwxr-xr-x 2 root root 4096 Oct 15 19:15 test-0

[root@iZ2zei0nwllapkwklisoncZ kafka-logs]#