不能使用类，因为它不是一个特征

我已按照教程进行操作here http://culttt.com/2014/01/13/advanced-validation-service-laravel-4/为 Laravel 构建验证服务。我现在在尝试从我的控制器之一调用验证器时遇到问题。我看到错误：

validController cannot use Portal\Service\Validation\Laravel\AppInstancesValidator - it is not a trait

这是我的控制器：

class validController extends BaseController {

   use \Portal\Service\Validation\Laravel\AppInstancesValidator;

   public function validateInstance() {
      $post = Input::all();

      $instVal = new AppInstancesValidator( App::make('validator'));

      return $instVal->with($post)->passes();
  }

}

和我的验证器：

namespace Portal\Service\Validation\Laravel;

use Portal\Service\Validation\ValidableInterface;

class AppInstancesValidator extends LaravelValidator implements ValidableInterface {


  protected $rules = array(
    'app_name' => 'required',
    'app_instance_name' => 'required',
    'app_instance_ip' => 'required|ip'
  );

}

尝试将use之前class宣言：

<?php // namespace Portal\Controllers;

use \Portal\Service\Validation\Laravel\AppInstancesValidator;

class validController extends BaseController {

    public function validateInstance() {}

}