Kafka Admin Client in Multi Threading

Question

I have Kafka client with the following code,

private AdminClient getKafkaClient() {
        final Map<String, Object> configs = new ConcurrentHashMap<>();
        configs.put(AdminClientConfig.BOOTSTRAP_SERVERS_CONFIG, "server-ip");
        return AdminClient.create(configs);
    }

This method invoked by multiple thread, and creates many admin client. So i wanted to keep in one instance and make use of it.

I've read an article for Singleton using Holder class with the below url,

Regarding static holder singleton pattern

Looks good to me, when i tried to implement issue setting config and can't create instance. Can any one suggest me best idea in my problem?

Thank you!

Singleton would work fine. And you don't need a concurrent Hashmap. Please show your actual stacktrace — OneCricketeer, Mar 02 '20 at 15:54
Alternatively, use a higher level framework like Spring Kafka or Akka Streams which can inject single instances for you — OneCricketeer, Mar 02 '20 at 15:55
The below config works and managed to get running. Thank you @cricket_007 — parrotjack, Mar 02 '20 at 16:34

score 1 · Answer 1 · answered Mar 02 '20 at 16:02

The following looks good?? I made it to work.

public class KafkaAdminManager {

    private ConnectionConfig connectionConfig;
    private static final Map<String, Object> configs =  new HashMap<>();

    public KafkaAdminManager(ConnectionConfig connectionConfig) {
        configs.put(AdminClientConfig.BOOTSTRAP_SERVERS_CONFIG, connectionConfig.getBootstrapServers());
        this.connectionConfig = connectionConfig;
    }

    private static class InstanceHolder {
        public static AdminClient instance = AdminClient.create(configs);
    }

    private KafkaAdminManager(){}

    public static AdminClient getInstance() {
        return InstanceHolder.instance;
    }

}

You don't necessarily need two classes, but looks fine – OneCricketeer Mar 02 '20 at 16:40 — OneCricketeer, Mar 02 '20 at 16:40
Thank you very much for your feedback. – parrotjack Mar 02 '20 at 17:41 — parrotjack, Mar 02 '20 at 17:41

Kafka Admin Client in Multi Threading

1 Answers1