Revision history [back]

One way to execute code exclusively for the initial clustered client in a Hazelcast Client Server system is by using the HazelcastClientInitialMembershipListener interface. This interface provides a method called init() which is called only once when the client initially connects to the Hazelcast cluster.

Here is an example code snippet:

public class MyHazelcastClientInitialMembershipListener implements HazelcastClientInitialMembershipListener {

    @Override
    public void init(InitialMembershipEvent event) {
        // Code to be executed exclusively for the initial clustered client
        System.out.println("Executing code exclusively for the initial clustered client");
    }

    @Override
    public void memberAdded(MembershipEvent event) {}

    @Override
    public void memberRemoved(MembershipEvent event) {}
}

To register this listener, you can use the HazelcastClientConfig object as follows:

HazelcastClientConfig config = new HazelcastClientConfig();
config.addListenerConfig(new ListenerConfig(new MyHazelcastClientInitialMembershipListener()));
HazelcastInstance hazelcastClient = HazelcastClient.newHazelcastClient(config);

With this configuration, the init() method of the MyHazelcastClientInitialMembershipListener class will be executed only once for the initial clustered client.