.protocols(Collections.singletonList(Protocol.H2_PRIOR_KNOWLEDGE))
        .build();

    Request request = new Request.Builder()
        .url("http://publicobject.com/helloworld.txt")
        .build();

    try (Response response = client.newCall(request).execute()) {
      System.out.println(response.body().string());
    }

    server.shutdown();
    socketFile.delete();
  }

You could create an API with a *path operation* that could trigger a request to an *external API* created by someone else (probably the same developer that would be *using* your API).

The process that happens when your API app calls the *external API* is named a "callback". Because the software that the external developer wrote sends a request to your API and then your API *calls back*, sending a request to an *external API* (that was probably created by the same developer).

        initRepoSession(configuration);
        return configuration;
    }

    protected void initRepoSession(ProjectBuildingRequest request) throws ComponentLookupException {
        File localRepo = new File(request.getLocalRepository().getBasedir());
        DefaultRepositorySystemSession repoSession = new DefaultRepositorySystemSession(h -> false);

Si una request entrante no se valida correctamente, se enviará un response `400`.

## `GZipMiddleware` { #gzipmiddleware }

Maneja responses GZip para cualquier request que incluya `"gzip"` en el header `Accept-Encoding`.

El middleware manejará tanto responses estándar como en streaming.

  }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testSpliteratorNullable() {
    initCollectionWithNullElement();
    assertFalse(collection.spliterator().hasCharacteristics(Spliterator.NONNULL));
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testSpliteratorNotImmutable_collectionAllowsAdd() {
    // If add is supported, verify that IMMUTABLE is not reported.

import okhttp3.MediaType;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import okhttp3.ResponseBody;
import okio.Buffer;
import okio.BufferedSource;
import okio.ForwardingSource;
import okio.Okio;
import okio.Source;

public final class Progress {

  public void run() throws Exception {
    Request request = new Request.Builder()
        .url("https://publicobject.com/helloworld.txt")

     *
     * @param request The repository request from which this cache was retrieved, must not be {@code null}.
     * @param key The key to use associate the data with, must not be {@code null}.
     * @param data The data to store in the cache, may be {@code null}.
     */
    void put(RepositoryRequest request, Object key, Object data);

    /**

The middleware responds to two particular types of HTTP request...

### CORS preflight requests { #cors-preflight-requests }

These are any `OPTIONS` request with `Origin` and `Access-Control-Request-Method` headers.

In this case the middleware will intercept the incoming request and respond with appropriate CORS headers, and either a `200` or `400` response for informational purposes.

    /**
     * Gets the appropriate web API manager for the given request.
     *
     * @param request The HTTP servlet request
     * @return The matching web API manager, or null if no match found
     */
    public WebApiManager get(final HttpServletRequest request) {
        for (final WebApiManager webApiManager : webApiManagers) {
            if (webApiManager.matches(request)) {
                return webApiManager;
            }

        .build()
  }

  @Test
  fun testRequestExternal() {
    assumeNetwork()

    val request = Request("https://www.google.com/robots.txt".toHttpUrl())

    val networkRequest =
      request
        .newBuilder()
        .build()

    val call = client.newCall(networkRequest)

    call.execute().use { response ->