* <i>only</i> if the caller knows that the collection does not contain any null elements.
   *
   * <p>This method returns the elements in the order they are returned by the collection's
   * iterator.
   *
   * <p>TODO(kevinb): support concurrently modified collections?
   *
   * @param c the collection for which to return an array of elements
   * @param array the array in which to place the collection elements

  /**
   * Returns the value associated with {@code key} in this cache, or {@code null} if there is no
   * cached value for {@code key}.
   *
   * @since 11.0
   */
  @CanIgnoreReturnValue // TODO(b/27479612): consider removing this?
  @Nullable V getIfPresent(@CompatibleWith("K") Object key);

  /**
   * Returns the value associated with {@code key} in this cache, obtaining that value from {@code

        if (crawlingInfoPager.id != null) {
            cb.query().docMeta().setId_Equal(crawlingInfoPager.id);
        }
        // TODO Long, Integer, String supported only.
        if (StringUtil.isNotBlank(crawlingInfoPager.sessionId)) {
            cb.query().setSessionId_Match(crawlingInfoPager.sessionId);
        }

          // if this is a concern we could add special cases for some known charsets (like utf8)
          // or we could avoid inputstreamreader and use the decoder api directly
          // TODO(lukes): in a real implementation we would need to handle overflow conditions
          int maxChars = (int) (size.get().intValue() * cs.newDecoder().maxCharsPerByte());
          char[] buffer = new char[maxChars];

Se houver alguma tarefa em segundo plano (abordada na seção [Tarefas em segundo plano](background-tasks.md){.internal-link target=_blank}, que você verá mais adiante), ela será executada *depois* de todo o middleware.

///

## Criar um middleware { #create-a-middleware }

Para criar um middleware, use o decorador `@app.middleware("http")` logo acima de uma função.

A função middleware recebe:

            "A duplicate name exists on the network.", "The network name cannot be found.", "ERRnomoreconn.", "The file exists.",
            "The parameter is incorrect.", "Too many Uids active on this session.",
            "The Uid is not known as a valid user identifier on this session.", "The pipe has been ended.",

            "A duplicate name exists on the network.", "The network name cannot be found.", "ERRnomoreconn.", "The file exists.",
            "The parameter is incorrect.", "Too many Uids active on this session.",
            "The Uid is not known as a valid user identifier on this session.", "The pipe has been ended.",

// errRPCAPIVersionUnsupported - unsupported rpc API version.
var errRPCAPIVersionUnsupported = errors.New("Unsupported rpc API version")

// errServerTimeMismatch - server times are too far apart.
var errServerTimeMismatch = errors.New("Server times are too far apart")

// errInvalidRange - returned when given range value is not valid.
var errInvalidRange = errors.New("Invalid range")

 * @author Charles Fry
 * @author Doug Lea ({@code ConcurrentHashMap})
 */
// TODO(kak): Consider removing @CanIgnoreReturnValue from this class.
@J2ktIncompatible
@GwtIncompatible
@SuppressWarnings({
  "GuardedBy", // TODO(b/35466881): Fix or suppress.
  "nullness", // too much trouble for the payoff
})
@NullUnmarked // TODO(cpovirk): Annotate for nullness.
final class MapMakerInternalMap<
        K,
        V,

///

## Headers duplicados { #duplicate-headers }

Es posible recibir headers duplicados. Eso significa, el mismo header con múltiples valores.

Puedes definir esos casos usando una lista en la declaración del tipo.

Recibirás todos los valores del header duplicado como una `list` de Python.

Por ejemplo, para declarar un header de `X-Token` que puede aparecer más de una vez, puedes escribir: