controller:

public function filtes()
{
    return array(
        'accessControl',
        'application.components.UserFilter',
    );
}

public function actionIndex()
{
    var_dump($this->filters()); // empty array
}

UserFilter:

class UserFilter extends CFilter
{
    public function init()
    {
        echo "init test";
    }

    public function preFilter($filterChain)
    {
        echo "filter test";

        return true;
    }
}