* Instead, use the {@code HashSet} constructor directly, taking advantage of <a
   * href="http://goo.gl/iz2Wi">"diamond" syntax</a>.
   *
   * <p>Overall, this method is not very useful and will likely be deprecated in the future.
   */
  public static <E extends @Nullable Object> HashSet<E> newHashSet(Iterable<? extends E> elements) {
    return (elements instanceof Collection)

   *       RuntimeException} (though {@code get} implementations are discouraged from throwing such
   *       exceptions).
   * </ul>
   *
   * <p>The overall principle is to continue to treat every checked exception as a checked
   * exception, every unchecked exception as an unchecked exception, and every error as an error. In