public static function createNew( $docType = null )
    {
        if ( ( $docType === null ) &&
             function_exists( 'get_called_class' ) )
        {
            $docType = get_called_class();
        }
        elseif ( $docType === null )
        {
            throw new phpillowRuntimeException( 'Invalid docType provided to createNew.' );
        }

        return new $docType();
    }