* invoke methods, they invoke methods on the {@code ForwardingBlockingDeque}.
 *
 * <p>The {@code standard} methods are not guaranteed to be thread-safe, even when all of the
 * methods that they depend on are thread-safe.
 *
 * @author Emily Soldal
 * @since 21.0 (since 14.0 as {@link com.google.common.collect.ForwardingBlockingDeque})
 */
@J2ktIncompatible
@GwtIncompatible