## 🏗️ Architecture & Design Patterns

### Core Design Principles
CoreLib follows a **utility-class pattern** where most functionality is exposed through static methods:

- **Assertion-based validation** - All methods validate inputs using `AssertionUtil.assertArgumentNotNull()` and `AssertionUtil.assertArgumentNotEmpty()`

* **Convertir des données** : depuis la requête vers les types requis.
* **Valider des données** : venant de chaque requête :
    * Générant automatiquement des **erreurs** renvoyées au client quand la donnée est invalide.
* **Documenter** l'API avec OpenAPI :
    * ce qui ensuite utilisé par les interfaces utilisateur automatiques de documentation interactive.

				enabled = false
			}
		}

		// No need to continue loading if the config is not enabled.
		if !enabled {
			continue
		}

		// Validate that client ID has not been duplicately specified.
		if seenClientIDs.Contains(p.ClientID) {
			return c, config.Errorf("Client ID %s is present with multiple OpenID configurations", p.ClientID)
		}

                        } catch (final SmbException se) {
                            if (LogStream.level >= 2) {
                                SmbTransport.log.println("Failed validate DC: " + dc_list[i]);
                                if (LogStream.level > 2) {
                                    se.printStackTrace(SmbTransport.log);
                                }
                            }

* the property
* the proxy
* the pull request
* the query
* the RAM
* the remote machine
* the status code
* the string
* the tag
* the web framework
* the wildcard
* to return
* to validate

////

//// tab | Info

            )

    def get_default(self) -> Any:
        if self.field_info.is_required():
            return Undefined
        return self.field_info.get_default(call_default_factory=True)

    def validate(
        self,
        value: Any,
        values: dict[str, Any] = {},  # noqa: B006
        *,
        loc: tuple[Union[int, str], ...] = (),
    ) -> tuple[Any, Union[list[dict[str, Any]], None]]:

            urlQueueService.offerAll(crawlerContext.sessionId, childList);
        }
    }

    /**
     * Validates whether the URL queue entry is valid for crawling.
     * @param urlQueue The URL queue entry to validate.
     * @return true if valid, false otherwise.
     */
    protected boolean isValid(final UrlQueue<?> urlQueue) {
        if (urlQueue == null || StringUtil.isBlank(urlQueue.getUrl())

Next it will convert and validate the data. So, when you use that `settings` object, you will have data of the types you declared (e.g. `items_per_user` will be an `int`).

### Use the `settings` { #use-the-settings }

        } finally {
            Thread.currentThread().setContextClassLoader(oldCL);
            System.setProperties(oldProps);
        }
    }

    protected int doInvoke(C context) throws Exception {
        validate(context);
        pushCoreProperties(context);
        pushUserProperties(context);
        setupGuiceClassLoading(context);
        configureLogging(context);
        createTerminal(context);

    * Swagger UI.
    * ReDoc.

---

Coming back to the previous code example, **FastAPI** will:

* Validate that there is an `item_id` in the path for `GET` and `PUT` requests.
* Validate that the `item_id` is of type `int` for `GET` and `PUT` requests.
    * If it is not, the client will see a useful, clear error.