App\Providers\PluginServiceProvider::registerClassAutoloader PHP Method

    protected function registerClassAutoloader($paths)
    {
        spl_autoload_register(function ($class) use($paths) {
            // traverse in registered plugin paths
            foreach ((array) array_keys($paths) as $namespace) {
                if ($namespace != '' && mb_strpos($class, $namespace) === 0) {
                    // parse real file path
                    $path = $paths[$namespace] . Str::replaceFirst($namespace, '', $class) . ".php";
                    $path = str_replace('\\', '/', $path);
                    if (file_exists($path)) {
                        // include class file if it exists
                        include $path;
                    }
                }
            }
        });
    }