*
   * <p><b>Note:</b> if {@code K} is an {@code enum} type, use {@link #newEnumMap} instead.
   *
   * <p><b>Note:</b> this method is now unnecessary and should be treated as deprecated. Instead,
   * use the {@code HashMap} constructor directly, taking advantage of <a
   * href="http://goo.gl/iz2Wi">"diamond" syntax</a>.
   *
   * @return a new, empty {@code HashMap}
   */

   *     future's result type {@code C}, see {@link DeferredCloser#eventuallyClose(Object,
   *     Executor)}.
   * @param closingExecutor the future's result will be closed on this executor
   * @deprecated Creating {@link Future}s of closeable types is dangerous in general because the
   *     underlying value may never be closed if the {@link Future} is canceled after its operation