The query parameter `q` is of type `str | None`, that means that it's of type `str` but could also be `None`, and indeed, the default value is `None`, so FastAPI will know it's not required.

/// note

FastAPI will know that the value of `q` is not required because of the default value `= None`.

Having `str | None` will allow your editor to give you better support and detect errors.

///

     *
     * @throws CrawlerSystemException if the office manager fails to stop
     */
    @PreDestroy
    public void destroy() {
        try {
            officeManager.stop();
        } catch (final OfficeException e) {
            throw new CrawlerSystemException("Failed to stop officeManager.", e);
        }
    }

    /**

    }

    /**
     * Stops a running scheduled job.
     *
     * @param form the edit form containing the ID of the job to stop
     * @return HTML response redirecting to the list page after stopping
     */
    @Execute
    @Secured({ ROLE })
    public HtmlResponse stop(final EditForm form) {
        verifyCrudMode(form.crudMode, CrudMode.DETAILS);
        final String id = form.id;

The fast food store has 8 processors (cashiers/cooks). While the concurrent burgers store might have had only 2 (one cashier and one cook).

But still, the final experience is not the best. 😞

---

This would be the parallel equivalent story for burgers. 🍔

For a more "real life" example of this, imagine a bank.

e{content:"\f18d"}.fa-stack-overflow:before{content:"\f16c"}.fa-stackpath:before{content:"\f842"}.fa-stamp:before{content:"\f5bf"}.fa-star:before{content:"\f005"}.fa-star-and-crescent:before{content:"\f699"}.fa-star-half:before{content:"\f089"}.fa-star-half-alt:before{content:"\f5c0"}.fa-star-of-david:before{content:"\f69a"}.fa-star-of-life:before{content:"\f621"}.fa-staylinked:before{content:"\f3f5"}.fa-steam:before{content:"\f1b6"}.fa-steam-square:before{content:"\f1b7"}.fa-steam-symbol:before...

Le paramètre de requête `q` a pour type `Union[str, None]` (ou `str | None` en Python 3.10), signifiant qu'il est de type `str` mais pourrait aussi être égal à `None`, et bien sûr, la valeur par défaut est `None`, donc **FastAPI** saura qu'il n'est pas requis.

/// note

**FastAPI** saura que la valeur de `q` n'est pas requise grâce à la valeur par défaut `= None`.

以下のアプリケーションを例にしてみましょう:

{* ../../docs_src/query_params_str_validations/tutorial001.py hl[9] *}

クエリパラメータ `q` は `Optional[str]` 型で、`None` を許容する `str` 型を意味しており、デフォルトは `None` です。そのため、FastAPIはそれが必須ではないと理解します。

/// note | 備考

FastAPIは、 `q` はデフォルト値が `=None` であるため、必須ではないと理解します。

`Optional[str]` における `Optional` はFastAPIには利用されませんが、エディターによるより良いサポートとエラー検出を可能にします。

///

## バリデーションの追加

이 응용 프로그램을 예로 들어보겠습니다:

{* ../../docs_src/query_params_str_validations/tutorial001.py hl[9] *}

쿼리 매개변수 `q`는 `Optional[str]` 자료형입니다. 즉, `str` 자료형이지만 `None` 역시 될 수 있음을 뜻하고, 실제로 기본값은 `None`이기 때문에 FastAPI는 이 매개변수가 필수가 아니라는 것을 압니다.

/// note | 참고

FastAPI는 `q`의 기본값이 `= None`이기 때문에 필수가 아님을 압니다.

`Optional[str]`에 있는 `Optional`은 FastAPI가 사용하는게 아니지만, 편집기에게 더 나은 지원과 오류 탐지를 제공하게 해줍니다.

///

## 추가 검증

        final ConstructorDesc ctor = beanDesc.getConstructorDesc();
        assertThat(ctor, is(notNullValue()));
        assertThat(ctor.getBeanDesc(), is(sameInstance(beanDesc)));
        assertThat(ctor.getConstructor(), is((Constructor) MyBean.class.getConstructor()));
        assertThat(ctor.getParameterTypes().length, is(0));
        assertThat(ctor.isPublic(), is(true));

#
### BEGIN INIT INFO
# Provides:          fess
# Required-Start:    $network $remote_fs $named
# Required-Stop:     $network $remote_fs $named
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Starts fess
# Description:       Starts fess using start-stop-daemon
### END INIT INFO

PATH=/bin:/usr/bin:/sbin:/usr/sbin
NAME=fess
DESC="Fess Server"
DEFAULT=/etc/default/$NAME