public static function filterFiles($args, $allowWildcards = true)
    {
        $files = array();
        foreach ($args as $arg) {
            if (file_exists($arg)) {
                $files[] = $arg;
            } else if ($allowWildcards && strpos($arg, '*') !== false) {
                $files = array_merge($files, glob($arg));
            }
        }
        return $files;
    }