@GwtCompatible
public enum MultisetFeature implements Feature<Multiset> {
  /**
   * Indicates that elements from {@code Multiset.entrySet()} update to reflect changes in the
   * backing multiset.
   */
  ENTRIES_ARE_VIEWS;

  @Override
  public Set<Feature<? super Multiset>> getImpliedFeatures() {
    return emptySet();
  }

  @Retention(RetentionPolicy.RUNTIME)
  @Inherited

    private int crc2 = 0;
    private int crc3 = 0;

    @Override
    protected void process(ByteBuffer bb) {
      if (finished) {
        throw new IllegalStateException(
            "The behavior of calling any method after calling hash() is undefined.");
      }
      while (bb.remaining() >= 16) {
        crc0 = computeForWord(crc0);
        crc1 = computeForWord(crc1);
        crc2 = computeForWord(crc2);

   * to all callers.
   *
   * If computing multiple values is problematic, use an appropriate concurrency mechanism in your
   * [computeIfAbsent] implementation. No locks are held while calling this function.
   */
  fun <T : Any> tag(
    type: KClass<T>,
    computeIfAbsent: () -> T,
  ): T

  /**
   * Returns the tag attached with [type] as a key. If it is absent, then [computeIfAbsent] is

# OAuth2 mit Passwort (und Hashing), Bearer mit JWT-Tokens { #oauth2-with-password-and-hashing-bearer-with-jwt-tokens }

Da wir nun über den gesamten Sicherheitsablauf verfügen, machen wir die Anwendung tatsächlich sicher, indem wir <abbr title="JSON Web Tokens">JWT</abbr>-Tokens und sicheres Passwort-Hashing verwenden.

Diesen Code können Sie tatsächlich in Ihrer Anwendung verwenden, die Passwort-Hashes in Ihrer Datenbank speichern, usw.

# OAuth2 con Password (y hashing), Bearer con tokens JWT { #oauth2-with-password-and-hashing-bearer-with-jwt-tokens }

Ahora que tenemos todo el flujo de seguridad, hagamos que la aplicación sea realmente segura, usando tokens <abbr title="JSON Web Tokens">JWT</abbr> y hashing de contraseñas seguras.

Este código es algo que puedes usar realmente en tu aplicación, guardar los hashes de las contraseñas en tu base de datos, etc.

    return getAndUpdate(key, x -> newValue);
  }

  /**
   * Copies all of the mappings from the specified map to this map. The effect of this call is
   * equivalent to that of calling {@code put(k, v)} on this map once for each mapping from key
   * {@code k} to value {@code v} in the specified map. The behavior of this operation is undefined
   * if the specified map is modified while the operation is in progress.

  @Partially.GwtIncompatible("AVAILABLE but requires exceptionType to be Throwable.class")
  public final <X extends Throwable> FluentFuture<V> catching(
      Class<X> exceptionType, Function<? super X, ? extends V> fallback, Executor executor) {
    return (FluentFuture<V>) Futures.catching(this, exceptionType, fallback, executor);
  }

  /**
   * Returns a {@code Future} whose result is taken from this {@code Future} or, if this {@code

Sie sollten niemals Klartext-Passwörter speichern, daher verwenden wir ein (gefaktes) Passwort-Hashing-System.

Wenn die Passwörter nicht übereinstimmen, geben wir denselben Fehler zurück.

#### Passwort-Hashing { #password-hashing }

„Hashing“ bedeutet: Konvertieren eines Inhalts (in diesem Fall eines Passworts) in eine Folge von Bytes (ein schlichter String), die wie Kauderwelsch aussieht.

Let's put that data in the Pydantic `UserInDB` model first.

You should never save plaintext passwords, so, we'll use the (fake) password hashing system.

If the passwords don't match, we return the same error.

#### Password hashing { #password-hashing }

"Hashing" means: converting some content (a password in this case) into a sequence of bytes (just a string) that looks like gibberish.

import org.junit.rules.TestRule
import org.junit.runner.Description
import org.junit.runners.model.Statement

/**
 * A log handler that records which log messages were published so that a calling test can make
 * assertions about them.
 */
class TestLogHandler(
  private val logger: Logger,
) : TestRule,
  BeforeEachCallback,
  AfterEachCallback {