@Override
    public String toString() {
        return new StringBuilder(110).append("ClickHouseLoadBalancingPolicy [name=").append(getClass().getSimpleName())
                .append(", scheduler=").append(getScheduler() != null).append("]@").append(hashCode()).toString();
    }
Schedules the {@code task} to run only when {@code current} run has been
completed/cancelled or does not exist.

@param current  current task, which could be null or in running status
@param task     scheduled task to run
@param interval interval between each run
@return future object representing the scheduled task, could be null when no
        scheduler available({@link #getScheduler()} returns null)
clickhouse-client/src/main/java/com/clickhouse/client/ClickHouseLoadBalancingPolicy.java