assertTrue(map.containsKey(key));

    assertTrue(map.remove(key, 0L));
    assertEquals(0L, map.get(key));
    assertFalse(map.containsKey(key));
  }

  public void testRemoveZeros() {
    AtomicLongMap<Object> map = AtomicLongMap.create();
    Set<Object> nonZeroKeys = new HashSet<>();
    for (int i = 0; i < ITERATIONS; i++) {
      Object key = new Object();
      long value = i % 2;