Fatal error: Uncaught Error: Using $this when not in object context in /var/www/html/php7cookbook/source/Application/Database/Connection.php:48 Stack trace: #0 /var/www/html/php7cookbook/source/chapter04/chap_04_oop_factory_pattern_example.php(7): Application\Database\Connection::factory() #1 {main} thrown in /var/www/html/php7cookbook/source/Application/Database/Connection.php on line 48