if (list.isEmpty()) {
            return null;
        }
        if (list.size() >= 2) {
            String msg = "The size of selected list is over 1: " + list.size();
            throw new FetchingOverSafetySizeException(msg, 1); // immediately caught by caller and translated
        }
        return list.get(0);
    }

    @Override

      throw new VerifyException(lenientFormat(errorMessageTemplate, errorMessageArgs));
    }
    return reference;
  }

  // TODO(kevinb): consider <T> T verifySingleton(Iterable<T>) to take over for
  // Iterables.getOnlyElement()

  private Verify() {}

                    <include name="**/InternalFutureFailureAccess.java" />
                  </fileset>
                </copy>
                <!-- Any manually written supersource should take priority over the original guava source, so we set overwrite=true. -->
                <copy toDir="${project.build.directory}/guava-gwt-sources" overwrite="true">
                  <fileset dir="src-super" />
                </copy>

                    for param in parameters
                    if param.get("required")
                }
                # Make sure required definitions of the same parameter take precedence
                # over non-required definitions
                all_parameters.update(required_parameters)
                operation["parameters"] = list(all_parameters.values())
            if method in METHODS_WITH_BODY:

### Documentación de la API { #api-docs }

Si vas a `/docs`, verás que tiene los **esquemas** para los datos a enviar en requests y recibir en responses:

<img src="/img/tutorial/generate-clients/image01.png">

Puedes ver esos esquemas porque fueron declarados con los modelos en la app.

Esa información está disponible en el **OpenAPI schema** de la app, y luego se muestra en la documentación de la API.

    Client->>Proxy: HTTPS Request<br/>Host: mysuperapp.com<br/>Path: /items

    Note over Proxy: Proxy adds forwarded headers

    Proxy->>Server: HTTP Request<br/>X-Forwarded-For: [client IP]<br/>X-Forwarded-Proto: https<br/>X-Forwarded-Host: mysuperapp.com<br/>Path: /items

    Note over Server: Server interprets headers<br/>(if --forwarded-allow-ips is set)

                        if (contentLength > maxLength) {
                            throw new MaxLengthExceededException("The content length (" + contentLength + " byte) is over " + maxLength
                                    + " byte. The url is " + robotTxtUrl);
                        }
                    }
                }

                if (httpEntity != null) {

            if (SpnegoHttpFilter.Constants.ALLOW_UNSEC_BASIC.equals(name)) {
                // SECURITY WARNING: Unsecure basic authentication is enabled by default.
                // This sends credentials in Base64 encoding over potentially unencrypted connections.
                // For production, it is STRONGLY RECOMMENDED to set spnego.allow.unsecure.basic to false
                // and use HTTPS or more secure authentication methods.

      return equivalence + ".wrap(" + reference + ")";
    }

    @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;
  }

  /**
   * Returns an equivalence over iterables based on the equivalence of their elements. More
   * specifically, two iterables are considered equivalent if they both contain the same number of

  public void forEach(LongConsumer consumer) {
    checkNotNull(consumer);
    for (int i = start; i < end; i++) {
      consumer.accept(array[i]);
    }
  }

  /**
   * Returns a stream over the values in this array, in order.
   *
   * @since 33.4.0 (but since 22.0 in the JRE flavor)
   */
  // If users use this when they shouldn't, we hope that NewApi will catch subsequent stream calls