if (ownerType != null && of(ownerType).isSubtypeOf(supertype)) {
        return true;
      }
    }
    return false;
  }

  /**
   * Returns the owner type of a {@link ParameterizedType} or enclosing class of a {@link Class}, or
   * null otherwise.
   */
  @CheckForNull
  private Type getOwnerTypeIfPresent() {
    if (runtimeType instanceof ParameterizedType) {