public function __construct(Locator $locator, Driver $driver)
{
$this->driver = $driver;
$this->locator = $locator;
parent::__construct('Item (:type) ":selector", filters :filters, found by driver ":driver"', array(':type' => $locator->type(), ':selector' => $locator->selector(), ':driver' => $driver->name, ':filters' => json_encode($locator->filters())));
}