}

  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
  public void testOffer_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> getQueue().offer(null));
    expectUnchanged();
    expectNullMissingWhenNullUnsupported("Should not contain null after unsupported offer(null)");
  }

            .compute(
                k3(),
                (k, v) -> {
                  assertEquals(k3(), k);
                  assertNull(v);
                  return null;
                }));
    expectUnchanged();
    assertEquals(getNumElements(), getMap().size());
  }

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE})
  @CollectionSize.Require(absent = ZERO)
  public void testCompute_presentToPresent() {

        getMultiset().setCount(e0(), 2, 3));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testSetCountConditional_oldCountTooSmallZero() {
    assertFalse(
        "setCount() with a too-small oldCount should return false",
        getMultiset().setCount(e0(), 0, 2));
    expectUnchanged();
  }

  @CollectionSize.Require(SEVERAL)

    expectUnchanged();
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testClear_unsupportedByEmptyCollection() {
    try {
      collection.clear();
    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }

      }
    }
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testSetValueNullUnsupported() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      assertThrows(NullPointerException.class, () -> entry.setValue(null));
      expectUnchanged();
    }
  }

    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testRemoveIf_alwaysTrueUnsupported() {
    assertThrows(UnsupportedOperationException.class, () -> collection.removeIf(x -> true));
    expectUnchanged();
    assertTrue(collection.contains(samples.e0()));
  }

public class MultimapRemoveAllTester<K, V> extends AbstractMultimapTester<K, V, Multimap<K, V>> {
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemoveAllAbsentKey() {
    assertEmpty(multimap().removeAll(k3()));
    expectUnchanged();
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemoveAllPresentKey() {
    assertContentsAnyOrder(multimap().removeAll(k0()), v0());

    assertThrows(UnsupportedOperationException.class, () -> getMap().clear());
    expectUnchanged();
  }

  @MapFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testClear_unsupportedByEmptyCollection() {
    try {
      getMap().clear();
    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }

    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_KEYS)
  public void testPutAllRejectsNullKey() {
    Multimap<K, V> source = getSubjectGenerator().create(mapEntry(null, v0()));
    assertThrows(NullPointerException.class, () -> multimap().putAll(source));
    expectUnchanged();
  }

  @MapFeature.Require(SUPPORTS_PUT)

    expectUnchanged();
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(ZERO)
  public void testClear_unsupportedByEmptyCollection() {
    try {
      collection.clear();
    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }