## Use case { #use-case }

For example, imagine that you want to return an HTTP status code of "OK" `200` by default.

But if the data didn't exist, you want to create it, and return an HTTP status code of "CREATED" `201`.

But you still want to be able to filter and convert the data you return with a `response_model`.

For those cases, you can use a `Response` parameter.

/// tip

This is probably not as important or necessary if you use `Annotated`.

///

Let's say that you want to declare the query parameter `q` as a required `str`.

And you don't need to declare anything else for that parameter, so you don't really need to use `Query`.

But you still need to use `Path` for the `item_id` path parameter. And you don't want to use `Annotated` for some reason.

We can use **OAuth2** to build that with **FastAPI**.

But let's save you the time of reading the full long specification just to find those little pieces of information you need.

Let's use the tools provided by **FastAPI** to handle security.

## How it looks { #how-it-looks }

    throw new InvalidObjectException("Use SerializedForm");
  }

  /**
   * Not supported. Use {@link #toImmutableSortedMultiset} instead. This method exists only to hide
   * {@link ImmutableMultiset#toImmutableMultiset} from consumers of {@code
   * ImmutableSortedMultiset}.
   *
   * @throws UnsupportedOperationException always
   * @deprecated Use {@link ImmutableSortedMultiset#toImmutableSortedMultiset}.

  LazyLogger(Class<?> ownerOfLogger) {
    this.loggerName = ownerOfLogger.getName();
  }

  Logger get() {
    /*
     * We use double-checked locking. We could the try racy single-check idiom, but that would
     * depend on Logger to not contain mutable state.
     *
     * We could use Suppliers.memoizingSupplier here, but I micro-optimized to this implementation

   * throws a {@link NullPointerException}.
   *
   * <p>To find the first non-null element in an iterable, use {@code Iterables.find(iterable,
   * Predicates.notNull())}. For varargs, use {@code Iterables.find(Arrays.asList(a, b, c, ...),
   * Predicates.notNull())}, static importing as necessary.
   *

    /**
     * The algorithm to use for the cipher.
     */
    protected String algorithm = BLOWFISH;

    /**
     * The transformation to use for the cipher.
     */
    protected String transformation = RSA;

    /**
     * The key to use for encryption/decryption.
     */
    protected String key;

    /**
     * The character set name to use for encoding/decoding strings.
     */

 *
 * @author mbechler
 *
 * <p>This interface is intended for internal use.</p>
 */
public interface SmbTransportPool {

    /**
     * Gets an SMB transport connection to the specified server.
     *
     * @param tf the CIFS context to use
     * @param name the server name or address
     * @param port the port number

   * types (or if the type is a non-variable type, like {@code String}), then code should almost
   * never use this method, preferring instead to call {@code requireNonNull} so as to benefit from
   * its runtime check.
   *
   * <p>An example use case for this method is in implementing an {@code Iterator<T>} whose {@code

{* ../../docs_src/query_params_str_validations/tutorial003.py hl[9] *}

## Ajouter des validations par expressions régulières

On peut définir une <abbr title="Une expression régulière, regex ou regexp est une suite de caractères qui définit un pattern de correspondance pour les chaînes de caractères.">expression régulière</abbr> à laquelle le paramètre doit correspondre :

{* ../../docs_src/query_params_str_validations/tutorial004.py hl[10] *}