* Returns the identity function.
   *
   * <p><b>Discouraged:</b> Prefer using a lambda like {@code v -> v}, which is shorter and often
   * more readable.
   */
  // implementation is "fully variant"; E has become a "pass-through" type
  @SuppressWarnings("unchecked")
  public static <E extends @Nullable Object> Function<E, E> identity() {
    return (Function<E, E>) IdentityFunction.INSTANCE;
  }

  // enum singleton pattern

 *
 * <ol>
 *   <li>Expose a public method, known as the <i>event subscriber</i>, which accepts a single
 *       argument of the type of event desired;
 *   <li>Mark it with a {@link Subscribe} annotation;
 *   <li>Pass itself to an EventBus instance's {@link #register(Object)} method.
 * </ol>
 *
 * <h2>Posting Events</h2>
 *
 * <p>To post an event, simply provide the event object to the {@link #post(Object)} method. The

///

## 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.

Whenever you pass exactly the same content (exactly the same password) you get exactly the same gibberish.

But you cannot convert from the gibberish back to the password.

### Why use password hashing { #why-use-password-hashing }

        ProtwordsItem newItem = new ProtwordsItem(0, "testNew");
        ProtwordsFile.ProtwordsUpdater updater = protwordsFile.new ProtwordsUpdater(newItem);

        // Write an existing item (should pass through)
        ProtwordsItem existingItem = new ProtwordsItem(10, "existing");
        ProtwordsItem result = updater.write(existingItem);

        assertNotNull(result);

Create a secret with private.key and public.crt files and pass that here. Ref: https://github.com/minio/minio/tree/master/docs/tls/kubernetes#2-create-kubernetes-secret certSecret: "" publicCrt: public.crt privateKey: private.key ## Trusted Certificates Settings for MinIO. Ref: https://min.io/docs/minio/linux/operations/network-encryption.html#third-party-certificate-authorities ## Bundle multiple trusted certificates into one secret and pass that here. Ref: https://github.com/minio/minio/tree/mas...

Create a secret with private.key and public.crt files and pass that here. Ref: https://github.com/minio/minio/tree/master/docs/tls/kubernetes#2-create-kubernetes-secret certSecret: "" publicCrt: public.crt privateKey: private.key ## Trusted Certificates Settings for MinIO. Ref: https://min.io/docs/minio/linux/operations/network-encryption.html#third-party-certificate-authorities ## Bundle multiple trusted certificates into one secret and pass that here. Ref: https://github.com/minio/minio/tree/mas...

Create a secret with private.key and public.crt files and pass that here. Ref: https://github.com/minio/minio/tree/master/docs/tls/kubernetes#2-create-kubernetes-secret certSecret: "" publicCrt: public.crt privateKey: private.key ## Trusted Certificates Settings for MinIO. Ref: https://min.io/docs/minio/linux/operations/network-encryption.html#third-party-certificate-authorities ## Bundle multiple trusted certificates into one secret and pass that here. Ref: https://github.com/minio/minio/tree/mas...

Create a secret with private.key and public.crt files and pass that here. Ref: https://github.com/minio/minio/tree/master/docs/tls/kubernetes#2-create-kubernetes-secret certSecret: "" publicCrt: public.crt privateKey: private.key ## Trusted Certificates Settings for MinIO. Ref: https://min.io/docs/minio/linux/operations/network-encryption.html#third-party-certificate-authorities ## Bundle multiple trusted certificates into one secret and pass that here. Ref: https://github.com/minio/minio/tree/mas...

Create a secret with private.key and public.crt files and pass that here. Ref: https://github.com/minio/minio/tree/master/docs/tls/kubernetes#2-create-kubernetes-secret certSecret: "" publicCrt: public.crt privateKey: private.key ## Trusted Certificates Settings for MinIO. Ref: https://min.io/docs/minio/linux/operations/network-encryption.html#third-party-certificate-authorities ## Bundle multiple trusted certificates into one secret and pass that here. Ref: https://github.com/minio/minio/tree/mas...

 *
 * <p>The common ways to get an instance of {@code Ordering} are:
 *
 * <ul>
 *   <li>Subclass it and implement {@link #compare} instead of implementing {@link Comparator}
 *       directly
 *   <li>Pass a <i>pre-existing</i> {@link Comparator} instance to {@link #from(Comparator)}
 *   <li>Use the natural ordering, {@link Ordering#natural}
 * </ul>
 *
 * <h4>Chaining</h4>
 *