public long getLastAccessTime() {
        return lastAccessTime;
    }
@Test
    public void testConstructorSetsLastAccessTime() {
        long lastAccessTime = iterator.getLastAccessTime();
        assertThat(lastAccessTime).isGreaterThan(System.currentTimeMillis() - TimeUnit.HOURS.toMillis(1));
        assertThat(lastAccessTime).isLessThanOrEqualTo(System.currentTimeMillis());
    }