*
     * @param <E> the element type of {@link Stack}
     * @return a new instance of {@link Stack}
     * @see Stack#Stack()
     */
    public static <E> Stack<E> newStack() {
        return new Stack<>();
    }

    /**
     * Creates and returns a new instance of {@link SynchronousQueue}.
     *
     * @param <E> the element type of {@link SynchronousQueue}