public static ClusterIdentifier getInstance(String hostsAndPorts, String username,
            String password) {
        return getInstance(hostsAndPorts, username, password, null);
    }
public static ClusterIdentifier getInstance(String hostsAndPorts, String username,
            String password) {
        return getInstance(hostsAndPorts, username, password, null);
    }
public static ClusterIdentifier getInstance ( String hostsAndPorts , String username , String password ) { return getInstance ( hostsAndPorts , username , password , null ) ; }
Helper method to get an instance of {@link ClusterIdentifier}.

@param hostsAndPorts
example {@code "localhost:9042,host2,host3:19042"}
@param username
username to authenticate against Cassandra cluster
@param password
password to authenticate against Cassandra cluster
@return
Helper method to get an instance of { @link ClusterIdentifier } .