public void testClear_unsupported() {
    assertThrows(UnsupportedOperationException.class, () -> collection.clear());
    expectUnchanged();
  }

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

  @Override
  public final @Nullable V put(K k, V v) {
    throw new UnsupportedOperationException();
  }

  @Override
  public final @Nullable V remove(Object o) {
    throw new UnsupportedOperationException();
  }

  @Override
  public final void putAll(Map<? extends K, ? extends V> map) {
    throw new UnsupportedOperationException();
  }

  @Override
  public final void clear() {

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class MultisetAddTester<E> extends AbstractMultisetTester<E> {
  @CollectionFeature.Require(absent = SUPPORTS_ADD)
  public void testAddUnsupported() {
    assertThrows(UnsupportedOperationException.class, () -> getMultiset().add(e0()));
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testAddMeansAddOne() {
    int originalCount = getMultiset().count(e0());

        Map<Object, Object> sourceMap = new LinkedHashMap<>();
        for (Entry<?, ?> entry : entries) {
          if (sourceMap.put(entry.getKey(), entry.getValue()) != null) {
            throw new UnsupportedOperationException("duplicate key");
          }
        }
        return ImmutableBiMap.copyOf(sourceMap);
      }
    },
    COPY_OF_ENTRIES {
      @Override

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

  @MapFeature.Require(absent = SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testComputeIfPresent_unsupportedPresent() {
    assertThrows(
        UnsupportedOperationException.class, () -> getMap().computeIfPresent(k0(), (k, v) -> v3()));

          .put(TimeoutException.class, e -> e instanceof TimeoutException)
          .put(UnsupportedCharsetException.class, e -> e instanceof UnsupportedCharsetException)
          .put(UnsupportedOperationException.class, e -> e instanceof UnsupportedOperationException)
          .put(VerifyException.class, e -> e instanceof VerifyException)
          .putAll(PlatformSpecificExceptionBatch.PLATFORM.exceptions())
          .buildOrThrow();

          .put(TimeoutException.class, e -> e instanceof TimeoutException)
          .put(UnsupportedCharsetException.class, e -> e instanceof UnsupportedCharsetException)
          .put(UnsupportedOperationException.class, e -> e instanceof UnsupportedOperationException)
          .put(VerifyException.class, e -> e instanceof VerifyException)
          .putAll(PlatformSpecificExceptionBatch.PLATFORM.exceptions())
          .buildOrThrow();

          .put(TimeoutException.class, e -> e instanceof TimeoutException)
          .put(UnsupportedCharsetException.class, e -> e instanceof UnsupportedCharsetException)
          .put(UnsupportedOperationException.class, e -> e instanceof UnsupportedOperationException)
          .put(VerifyException.class, e -> e instanceof VerifyException)
          .putAll(PlatformSpecificExceptionBatch.PLATFORM.exceptions())
          .buildOrThrow();

          .put(TimeoutException.class, e -> e instanceof TimeoutException)
          .put(UnsupportedCharsetException.class, e -> e instanceof UnsupportedCharsetException)
          .put(UnsupportedOperationException.class, e -> e instanceof UnsupportedOperationException)
          .put(VerifyException.class, e -> e instanceof VerifyException)
          .putAll(PlatformSpecificExceptionBatch.PLATFORM.exceptions())
          .buildOrThrow();

    return delegate().lastEntry();
  }

  @Override
  public @Nullable Entry<E> pollFirstEntry() {
    throw new UnsupportedOperationException();
  }

  @Override
  public @Nullable Entry<E> pollLastEntry() {
    throw new UnsupportedOperationException();
  }

  @Override
  public SortedMultiset<E> headMultiset(E upperBound, BoundType boundType) {