Now let's **refactor** this app a bit to increase **security** and **versatility**.

If you check the previous app, in the UI you can see that, up to now, it lets the client decide the `id` of the `Hero` to create. 😱

          return Optional.absent();
        }
        result += sizeIfKnown.get();
        if (result < 0) {
          // Overflow (or one or more sources that returned a negative size, but all bets are off in
          // that case)
          // Can't represent anything higher, and realistically there probably isn't anything that
          // can actually be done anyway with the supposed 8+ exbibytes of data the source is

    assertLockNotHeld()

    val connection = this.connection
    if (connection != null) {
      connection.assertLockNotHeld()
      val toClose: Socket? =
        connection.withLock {
          // Sets this.connection to null.
          releaseConnectionNoEvents()
        }
      if (this.connection == null) {
        toClose?.closeQuietly()
        eventListener.connectionReleased(this, connection)

            Range.atLeast(3),
            Range.closed(4, 6),
            Range.closedOpen(1, 3),
            Range.openClosed(5, 7),
            Range.open(3, 4));
    subsets:
    for (Set<Range<Integer>> subset : Sets.powerSet(ranges)) {
      assertEquals(TreeRangeSet.create(subset), ImmutableRangeSet.unionOf(subset));

      RangeSet<Integer> mutable = TreeRangeSet.create();

			Code: "BadRequest",
			Description: fmt.Sprintf("An unsupported API call for method: %s at '%s'",
				r.Method, r.URL.Path),
			HTTPStatusCode: http.StatusBadRequest,
		}, r.URL)
	}
}

// gets host name for current node
func getHostName(r *http.Request) (hostName string) {
	if globalIsDistErasure {
		hostName = globalLocalNodeName
	} else {
		hostName = r.Host
	}
	return hostName
}

      apply {
        this.message = message
      }

    open fun handshake(handshake: Handshake?) =
      apply {
        this.handshake = handshake
      }

    /**
     * Sets the header named [name] to [value]. If this request already has any headers
     * with that name, they are all replaced.
     */
    open fun header(
      name: String,
      value: String,
    ) = apply {

    addAll(list, elements);
    return list;
  }

  public static <E extends @Nullable Object> List<E> copyToList(E[] elements) {
    return copyToList(asList(elements));
  }

  // Clone of Sets.newLinkedHashSet
  public static <E extends @Nullable Object> Set<E> copyToSet(Iterable<? extends E> elements) {
    Set<E> set = new LinkedHashSet<>();
    addAll(set, elements);
    return set;
  }

// are equal, false otherwise
func isETagEqual(left, right string) bool {
	if strings.TrimSpace(right) == "*" {
		return true
	}
	return canonicalizeETag(left) == canonicalizeETag(right)
}

// setPutObjHeaders sets all the necessary headers returned back
// upon a success Put/Copy/CompleteMultipart/Delete requests
// to activate delete only headers set delete as true

 * and it should be appropriately marked with `@file:Incubating`.
 *
 * When the target method of an extension functions is de-incubated, removing at a later point is a breaking change.
 * The corresponding extension function gets automatically de-incubated during source generation.
 * But the same applies to the implicit file class, and it has to be de-incubated when any
 * extension function it contains is de-incubated.
 */
private

import static com.google.common.collect.Multimaps.synchronizedMultimap;
import static com.google.common.collect.ReflectionFreeAssertThrows.assertThrows;
import static com.google.common.collect.Sets.newHashSet;
import static com.google.common.collect.testing.Helpers.mapEntry;
import static com.google.common.collect.testing.IteratorFeature.MODIFIABLE;
import static com.google.common.truth.Truth.assertThat;