public void add(T element) {
        Preconditions.checkNotNull(element);
        if (elements.add(element) && elements.size() > maxSize) {
            elements.poll();
        }
    }
@Test
    void testQueueWithMaxSize0() {
        final BoundedFIFOQueue<Integer> testInstance = new BoundedFIFOQueue<>(0);
        assertThat(testInstance).isEmpty();
        testInstance.add(1);
        assertThat(testInstance).isEmpty();
    }