@VisibleForTesting
  static WildcardType supertypeOf(Type lowerBound) {
    return new WildcardTypeImpl(new Type[] {lowerBound}, new Type[] {Object.class});
  }

  /**
   * Returns a human-readable string representation of {@code type}.
   *
   * <p>The format is subject to change.
   */
  static String toString(Type type) {
    return (type instanceof Class) ? ((Class<?>) type).getName() : type.toString();

 * <td>{@link #base16()}
 * <td>0-9 A-F
 * <td>2.00
 * <td>N/A
 * <td>Traditional hexadecimal. Defaults to upper case.
 * <tr>
 * <td>{@link #base32()}
 * <td>A-Z 2-7
 * <td>1.60
 * <td>=
 * <td>Human-readable; no possibility of mixing up 0/O or 1/I. Defaults to upper case.
 * <tr>
 * <td>{@link #base32Hex()}
 * <td>0-9 A-V
 * <td>1.60
 * <td>=

    } else {
      addPendingString(builder); // delegates to addDoneString if future completes midway
    }
    return builder.append("]").toString();
  }

  /**
   * Provide a human-readable explanation of why this future has not yet completed.
   *
   * @return null if an explanation cannot be provided (e.g. because the future is done).
   * @since 23.0
   */
  @CheckForNull

          @Override
          public void run() {
            delegateForDelayedRuntimeException.set("Should never be seen");
          }
        };

    /** All the futures, together with human-readable names for use by {@link #smartToString}. */
    final ImmutableList<TestFuture> allFutures =
        ImmutableList.of(
            new TestFuture(doneSuccess, "doneSuccess", doNothing),

          @Override
          public void run() {
            delegateForDelayedRuntimeException.set("Should never be seen");
          }
        };

    /** All the futures, together with human-readable names for use by {@link #smartToString}. */
    final ImmutableList<TestFuture> allFutures =
        ImmutableList.of(
            new TestFuture(doneSuccess, "doneSuccess", doNothing),

--nx?a!.&bp?de?go?oc?ti?vg??boat??b!.&a&ci&sum?tilop??i&c&arcomed?neic??golo&ce?ncet??m&edaca?onoce??rt&ap?sudni??vilob??n&egidni?icidem??serpme?tsiver?vitarepooc??b&ew?og??dulas?e&rbmon?tr&a?op&ed?snart????g&olb?ro??ikiw?l&a&noi&canirulp?seforp??rutan??im??moc?o&fni?lbeup?rga?tneimivom??saiciton?t&askt?en?ni??ude?vt??h?iew?olg??c!.&bew?cer?dr&c,rac,?esabapus,gro?ipym,l&im?per:.di,,?m&o&c!.topsgolb,?n??rif??ofni?s&egap&dael,l,?tra??t&4n,en?ilperdellawerif:.di,,ni??ude?vog??a?e?in?mara?s&edarb?ic...