* thrown or a simple string message. In addition, a problem carries a hint about its source, e.g. the settings file
 * that exhibits the problem.
 *
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services} instead
 */
@Deprecated(since = "4.0.0")
class DefaultProblem implements Problem {

    private final String source;

    private final int lineNumber;

Por ejemplo, vamos a añadir <a href="https://github.com/Rebilly/ReDoc/blob/master/docs/redoc-vendor-extensions.md#x-logo" class="external-link" target="_blank">la extensión OpenAPI de ReDoc para incluir un logo personalizado</a>.

### **FastAPI** normal

Primero, escribe toda tu aplicación **FastAPI** como normalmente:

import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

/**
 * Base class for services that can implement {@link #startUp}, {@link #run} and {@link #shutDown}
 * methods. This class uses a single thread to execute the service; consider {@link AbstractService}
 * if you would like to manage any threading manually.
 *
 * @author Jesse Wilson
 * @since 1.0
 */
@GwtIncompatible
@J2ktIncompatible

/**
 * A {@link ListenableFuture} whose result can be set by a {@link #set(Object)}, {@link
 * #setException(Throwable)} or {@link #setFuture(ListenableFuture)} call. It can also, like any
 * other {@code Future}, be {@linkplain #cancel cancelled}.
 *
 * <p>{@code SettableFuture} is the recommended {@code ListenableFuture} implementation when your

También puedes declarar responses adicionales con sus modelos, códigos de estado, etc.

Hay un capítulo entero en la documentación sobre ello, puedes leerlo en [Responses Adicionales en OpenAPI](additional-responses.md){.internal-link target=_blank}.

## OpenAPI Extra

Cuando declaras una *path operation* en tu aplicación, **FastAPI** genera automáticamente los metadatos relevantes sobre esa *path operation* para incluirlos en el esquema de OpenAPI.

Para hacerlo, usa el type hint estándar de Python <a href="https://docs.python.org/3/library/typing.html#typing.Union" class="external-link" target="_blank">`typing.Union`</a>:

/// note | Nota

/**
 * A descriptor for a <i>discrete</i> {@code Comparable} domain such as all {@link Integer}
 * instances. A discrete domain is one that supports the three basic operations: {@link #next},
 * {@link #previous} and {@link #distance}, according to their specifications. The methods {@link
 * #minValue} and {@link #maxValue} should also be overridden for bounded types.
 *

    return new NullRemovalListener<>();
  }

  /** Type-inferring factory method for creating a {@link QueuingRemovalListener}. */
  @GwtIncompatible // ConcurrentLinkedQueue
  static <K, V> QueuingRemovalListener<K, V> queuingRemovalListener() {
    return new QueuingRemovalListener<>();
  }

  /** Type-inferring factory method for creating a {@link CountingRemovalListener}. */
  static <K, V> CountingRemovalListener<K, V> countingRemovalListener() {

        @Throws(IOException::class)
        override fun writeTo(sink: BufferedSink) {
          delegate().writeTo(uppercaseSink(sink).buffer())
        }
      }
    return request
      .newBuilder()
      .method(request.method, uppercaseBody)
      .build()
  }

  private fun uppercaseSink(sink: Sink): Sink =
    object : ForwardingSink(sink) {
      @Throws(IOException::class)
      override fun write(

 * collections are:
 *
 * <ul>
 *   <li>{@link #asMap}, mentioned above
 *   <li>{@link #keys}, {@link #keySet}, {@link #values}, {@link #entries}, which are similar to the
 *       corresponding view collections of {@link Map}
 *   <li>and, notably, even the collection returned by {@link #get get(key)} is an active view of
 *       the values corresponding to {@code key}
 * </ul>
 *