@Test
public void doEviction() {

  cache.put("a", "b", TimeUnit.MILLISECONDS, 0);
  cache.put("c", "d", TimeUnit.MILLISECONDS, 0);
  try {
    Thread.sleep(3);
  } catch (InterruptedException e) {
  }
  cache.doEviction();
  verify(evictionListener).onEviction("a", "b");
  verify(evictionListener).onEviction("c", "d");
  assertEquals(cache.size(), 0);
}