Core/Core/Core.php
public static function getInstance(Container $container = null)
    {
        if (null === self::$instance) {
            self::$instance = new Core($container);
        }
        return self::$instance;
    }
public static function getInstance(Container $container = null)
    {
        if (null === self::$instance) {
            self::$instance = new Core($container);
        }
        return self::$instance;
    }
public static function getInstance ( Container $ container = null ) { if ( null === self :: $ instance ) { self :: $ instance = new Core ( $ container ) ; } return self :: $ instance ; }
Get singleton instance of Core class.

@param Container|null $container
@return Core
Get singleton instance of Core class .