Hazelcast IdGenerator creates cluster-wide unique IDs. Generated IDs are long type primitive values between 0 and Long.MAX_VALUE . Id generation occurs almost at the speed of AtomicLong.incrementAndGet() . Generated IDs are unique during the life cycle of the cluster. If the entire cluster is restarted, IDs start from 0 again.

import com.hazelcast.core.IdGenerator;
import com.hazelcast.core.Hazelcast;

IdGenerator idGenerator = Hazelcast.getIdGenerator("customer-ids");
long id = idGenerator.newId();