private function internalFilterHooks($key, $value, $type = 'input')
    {
        $hook = '';
        switch (trim(strtolower($type))) {
            case 'output':
                $hook = 'filterOutputHook';
                break;
            case 'remove':
                $hook = 'filterRemoveHook';
                break;
            case 'input':
                $hook = 'filterInputHook';
                break;
        }
        if ($hook && method_exists($this, $hook)) {
            $result = $this->$hook($key, $value);
            if ($result !== true && $result !== null) {
                return false;
            }
        }
        return true;
    }