protected function initializeFieldName()
    {
        $this->fieldName = $this->arguments['field'];

        if (empty($this->fieldName)
            && $this->fieldService->fieldContextExists()
        ) {
            $this->fieldName = $this->fieldService
                ->getCurrentField()
                ->getName();
        }

        if (null === $this->fieldName) {
            throw EntryNotFoundException::classViewHelperFieldNotFound($this->arguments['name']);
        }
    }