@Override
    public String toString() {
        return new StringBuilder("ClickHouseCluster [name=").append(clusterName).append(", checking=")
                .append(checking.get()).append(", index=").append(index.get()).append(", lock=r")
                .append(lock.getReadHoldCount()).append('w').append(lock.getWriteHoldCount()).append(", nodes=")
                .append(nodes.size()).append(", faulty=").append(faultyNodes.size()).append(", policy=")
                .append(policy.getClass().getSimpleName()).append("]@").append(hashCode()).toString();
    }
Constructs cluster object using policy and list of nodes. It could be slow
when {@link ClickHouseClientOption#AUTO_DISCOVERY} is enabled.

@param cluster non-null cluster name
@param nodes   list of nodes
clickhouse-client/src/main/java/com/clickhouse/client/ClickHouseCluster.java