如何在Java中创建Kafka ZKStringSerializer?
在搜索如何通过API创建卡夫卡主题时,我在Scala中找到了以下示例:如何在Java中创建Kafka ZKStringSerializer?,java,scala,apache-kafka,Java,Scala,Apache Kafka,在搜索如何通过API创建卡夫卡主题时,我在Scala中找到了以下示例: import kafka.admin.AdminUtils import kafka.utils.ZKStringSerializer import org.I0Itec.zkclient.ZkClient // Create a ZooKeeper client val sessionTimeoutMs = 10000 val connectionTimeoutMs = 10000 val zkClient = new
import kafka.admin.AdminUtils
import kafka.utils.ZKStringSerializer
import org.I0Itec.zkclient.ZkClient
// Create a ZooKeeper client
val sessionTimeoutMs = 10000
val connectionTimeoutMs = 10000
val zkClient = new ZkClient("zookeeper1:2181", sessionTimeoutMs,
connectionTimeoutMs, ZKStringSerializer)
// Create a topic with 8 partitions and a replication factor of 3
val topicName = "myTopic"
val numPartitions = 8
val replicationFactor = 3
val topicConfig = new Properties
AdminUtils.createTopic(zkClient, topicName,
numPartitions, replicationFactor, topicConfig)
资料来源:
最后一个argZKStringSerializer
显然是一个Scala对象。我不清楚如何使这个示例在Java中工作
这篇文章在Clojure中提出了同样的问题,答案是:
ZKStringSerializer$/MODULE$
在Java中(我认为)可以转换为:
ZKStringSerializer$.MODULE$
但是,当我尝试这个(或任何数量的其他变体)时,它们都不会编译。编译错误是:
KafkaTopicCreator.java:[16,18] cannot find symbol
symbol: variable ZKStringSerializer$
location: class org.sample.KafkaTopicCreator
我正在使用kafka_2.9.2-0.8.1.1和Java 8。对于Java,请尝试以下操作: 下面的第一个导入语句
import kafka.utils.ZKStringSerializer$;
按以下方式为ZkClient创建对象
String zkHosts = "127.0.0.1:2181"; //If more than one zookeeper then "127.0.0.1:2181,127.0.0.2:2181"
ZkClient zkClient = new ZkClient(zkHosts, 10000, 10000, ZKStringSerializer$.MODULE$);
AdminUtils.createTopic(zkClient, myTopic, 10, 1, new Properties());
上述代码不适用于kafka>0.9,因为api已更改, 对于kafka>0.9,请使用以下代码
import java.util.Properties;
import kafka.admin.AdminUtils;
import kafka.utils.ZKStringSerializer$;
import kafka.utils.ZkUtils;
import org.I0Itec.zkclient.ZkClient;
import org.I0Itec.zkclient.ZkConnection;
public class KafkaTopicCreationInJava
{
public static void main(String[] args) throws Exception {
ZkClient zkClient = null;
ZkUtils zkUtils = null;
try {
String zookeeperHosts = "192.168.20.1:2181"; // If multiple zookeeper then -> String zookeeperHosts = "192.168.20.1:2181,192.168.20.2:2181";
int sessionTimeOutInMs = 15 * 1000; // 15 secs
int connectionTimeOutInMs = 10 * 1000; // 10 secs
zkClient = new ZkClient(zookeeperHosts, sessionTimeOutInMs, connectionTimeOutInMs, ZKStringSerializer$.MODULE$);
zkUtils = new ZkUtils(zkClient, new ZkConnection(zookeeperHosts), false);
String topicName = "testTopic";
int noOfPartitions = 2;
int noOfReplication = 3;
Properties topicConfiguration = new Properties();
AdminUtils.createTopic(zkUtils, topicName, noOfPartitions, noOfReplication, topicConfiguration);
} catch (Exception ex) {
ex.printStackTrace();
} finally {
if (zkClient != null) {
zkClient.close();
}
}
}
}