* {@code get(null)}, {@code keySet().contains(null)} or {@code remove(null)}.
   */
  ALLOWS_NULL_KEY_QUERIES,
  ALLOWS_NULL_KEYS(ALLOWS_NULL_KEY_QUERIES),
  /**
   * The map does not throw {@code NullPointerException} on calls such as {@code
   * containsValue(null)}, {@code values().contains(null)} or {@code values().remove(null)}.
   */
  ALLOWS_NULL_VALUE_QUERIES,
  ALLOWS_NULL_VALUES(ALLOWS_NULL_VALUE_QUERIES),

  }

  public void testRemove() {
    TestMap map = new TestMap();
    map.put("foo", 1);
    assertFalse(map.remove("foo", 2));
    assertFalse(map.remove("bar", 1));
    assertEquals(Integer.valueOf(1), map.get("foo"));
    assertTrue(map.remove("foo", 1));
    assertTrue(map.isEmpty());
  }

  public void testReplace() {
    TestMap map = new TestMap();
    map.put("foo", 1);

        if (cycle != null) {
            // remove edge which introduced cycle
            removeEdge(from, to);
            throw new CycleDetectedException(
                    "Edge between '" + from.label + "' and '" + to.label + "' introduces to cycle in the graph", cycle);
        }
    }

    void removeEdge(Vertex from, Vertex to) {
        from.children.remove(to);
        to.parents.remove(from);
    }

    throw new UnsupportedOperationException();
  }

  @CanIgnoreReturnValue
  @Override
  public final boolean remove(@Nullable Object element) {
    return remove(element, 1) > 0;
  }

  @CanIgnoreReturnValue
  @Override
  public int remove(@Nullable Object element, int occurrences) {
    throw new UnsupportedOperationException();
  }

  @CanIgnoreReturnValue
  @Override

    return delegate().hasNext();
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public T next() {
    return delegate().next();
  }

  @Override
  public void remove() {
    delegate().remove();
  }

        } catch (final IndexOutOfBoundsException e) {
            throw new NoSuchElementException("index=" + index);
        }
    }

    @Override
    public void remove() {
        throw new ClUnsupportedOperationException("remove");
    }

        AvPair result = AvPairs.get(pairs, AvPair.MsvAvFlags);
        assertNull(result, "Should return null for empty list");
    }

    /**
     * Test remove method
     */
    @Test
    @DisplayName("Remove should delete all occurrences of type")
    void testRemove() {
        List<AvPair> pairs = new LinkedList<>();
        AvFlags flags1 = new AvFlags(0x11111111);

    assertEquals(Multisets.immutableEntry(k0(), 1), itr.next());
    itr.remove();
    assertTrue(multimap().isEmpty());
  }

  @CollectionSize.Require(SEVERAL)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testKeysEntrySetRemove() {
    resetContainer(mapEntry(k0(), v0()), mapEntry(k0(), v1()), mapEntry(k1(), v0()));
    assertTrue(multimap().keys().entrySet().remove(Multisets.immutableEntry(k0(), 2)));

   * Thus, calls like asMap().values().remove(someSet) are safe because they are comparing a set to
   * a collection of other sets.
   */
  @SuppressWarnings("CollectionUndefinedEquality")
  public void testValuesRemove() {
    resetContainer(mapEntry(k0(), v0()), mapEntry(k1(), v0()), mapEntry(k0(), v3()));
    assertTrue(multimap().asMap().values().remove(singleton(v0())));
    assertEquals(2, multimap().size());

                    // Stop async notification monitoring
                    stopAsyncNotificationMonitoring(registration.getRegistrationId());

                    registrations.remove(registration.getRegistrationId());
                    listeners.remove(registration.getRegistrationId());

                    log.info("Successfully unregistered witness: {}", registration.getRegistrationId());
                } else {