php class Test public static function test_load file if is_file _SERVE

<?php
class Test
{
   public static function test_load($file)
    {
        if (is_file( $_SERVER['DOCUMENT_ROOT']. '/' . $file . '.php')) {
            return require($_SERVER['DOCUMENT_ROOT'].'/' . $file . '.php');
        } else {
            echo 'Нет такогофайла';
            return false;
        }
    }
}

$trololo = new Test();
$trololo -> test_load('file');
?>