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Is this correct use of Exception handling in PHP / Symfony2
class ExampleService{
    // ...
    public function getValueByUser($user)
    {
        $result = $this->em->getRepository('SomeBundle:SomeEntity')->getValue($user);
        if (!$result instanceof EntitySomeEntity) {
            throw new ExceptionInvalidArgumentException("no value found for that user");
        }
        return $result;
    }
}

// ...
$ExampleService = $this->get('example_serivce');

$value = $ExampleService->getValueByUser($user);

class UserService
{
    public function find($id)
    {
        return $this->em->getRepository('UserBundle:User')->find($id);
    }
}

class UserController
{
    public function viewAction($id)
    {
        $user = $this->get('user.service')->find($id);
        if (!$user) {
            throw $this->createNotFoundException(
                $this->get('translator')->trans('user.not_found')
            );
        }
        // ...
    }
}