/**
     * @throws Exception
     */
    @Test
    public void testGetFirstEntry() throws Exception {
        assertThat(list.getFirstEntry(), is(nullValue()));
        list.addFirst("1");
        assertThat(list.getFirstEntry().getElement(), is("1"));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testGetFirst() throws Exception {
        try {

     * Returns the first element.
     *
     * @return the first element
     */
    public E getFirst() {
        if (isEmpty()) {
            throw new NoSuchElementException();
        }
        return getFirstEntry().element;
    }

    /**
     * Returns the last element.
     *
     * @return the last element
     */
    public E getLast() {
        if (isEmpty()) {

        final List<TimeoutTask> expiredTask = new ArrayList<>();
        if (timeoutTaskList.isEmpty()) {
            return expiredTask;
        }
        for (SLinkedList<TimeoutTask>.Entry e = timeoutTaskList.getFirstEntry(); e != null; e = e.getNext()) {
            final TimeoutTask task = e.getElement();
            if (task.isCanceled()) {
                e.remove();
            } else if (!task.isStopped() && task.isExpired()) {