* This exception is typically thrown during authentication or user lookup operations
 * when the specified user does not exist in the system.
 */
public class FessUserNotFoundException extends FessSystemException {

    /** Serial version UID for serialization compatibility */
    private static final long serialVersionUID = 1L;

    /**
     * Constructs a new FessUserNotFoundException with the specified username.
     *

    * De ce fait, en utilisant FastAPI...

    //                                                                          Definition
    //                                                                          ==========
    /** The serial version UID for object serialization. (Default) */
    private static final long serialVersionUID = 1L;
    private final FessUser user;

    // ===================================================================================

 * query is malformed, contains invalid syntax, or violates query constraints.
 */
public class InvalidQueryException extends FessSystemException {

    /** Serial version UID for serialization */
    private static final long serialVersionUID = 1L;

    /** Message code for localized error messages */
    private final transient VaMessenger<FessMessages> messageCode;

    /**

///

Dessa forma:

* Este código de status será retornado na resposta.
* Será documentado como tal no esquema OpenAPI (e, portanto, nas interfaces do usuário):

<img src="/img/tutorial/response-status-code/image01.png">

/// note | Nota

 * such as configuration errors, initialization failures, or critical runtime issues.
 */
public class FessSystemException extends RuntimeException {

    /** Serial version UID for serialization compatibility */
    private static final long serialVersionUID = 1L;

    /**
     * Constructs a new FessSystemException with the specified detail message and cause.
     *

import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
final class SingletonImmutableSet<E> extends ImmutableSet<E> {
  // We deliberately avoid caching the asList and hashCode here, to ensure that with

Sin embargo, podemos declarar el esquema esperado para el cuerpo del request.

### Tipo de contenido personalizado de OpenAPI

  private static Runnable runnableThrowing(RuntimeException e) {
    return new Runnable() {
      @Override
      public void run() {
        throw e;
      }
    };
  }

  @SuppressWarnings("serial")
  private static class SampleCheckedException extends Exception {}

import com.google.common.base.Preconditions;
import java.util.Spliterator;

/**
 * Implementation of {@link ImmutableList} with exactly one element.
 *
 * @author Hayward Chan
 */
@GwtCompatible
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
final class SingletonImmutableList<E> extends ImmutableList<E> {

  final transient E element;

  SingletonImmutableList(E element) {