App.php
public static function init()
    {
        self::$_app = new self();
        self::$_app->_initConstant();

        require(PATH_LI . DIRECTORY_SEPARATOR . 'Function.php');
        return self::$_app;
    }
public static function init()
    {
        self::$_app = new self();
        self::$_app->_initConstant();

        require(PATH_LI . DIRECTORY_SEPARATOR . 'Function.php');
        return self::$_app;
    }
init app
@return App the app instance