@SuppressWarnings("unchecked") // unsafe, but Javadoc warns about it
        K k = (K) key;
        return function.apply(k);
      } else {
        return null;
      }
    }

    @Override
    public @Nullable V remove(@Nullable Object key) {
      if (backingSet().remove(key)) {
        @SuppressWarnings("unchecked") // unsafe, but Javadoc warns about it
        K k = (K) key;

        verify(tree, times(1)).close();
    }

    @Test
    @DisplayName("unwrap: returns self for compatible type and throws for incompatible")
    @SuppressWarnings({ "rawtypes", "unchecked" })
    void testUnwrap() {
        SmbSessionImpl session = newSession();

        // Happy path: ask for SmbSession and SmbSessionInternal
        assertSame(session, session.unwrap(SmbSessionInternal.class));

  }

  // Pretend the comparator can compare anything. If it turns out it can't
  // compare two elements, it'll throw a CCE. Only methods that are specified to
  // throw CCE should call this.
  @SuppressWarnings("unchecked")
  Comparator<Object> unsafeComparator() {
    return (Comparator<Object>) comparator;
  }

  RegularImmutableSortedSet<E> getSubSet(int newFromIndex, int newToIndex) {

    ReferenceEntry<Object, Object> entry = segment.getEntry(one, hash);
    ReferenceEntry<Object, Object> newEntry = segment.copyEntry(entry, null);
    table.set(index, newEntry);

    @SuppressWarnings("unchecked")
    LoadingValueReference<Object, Object> valueReference =
        (LoadingValueReference) newEntry.getValueReference();
    assertThat(valueReference.futureValue.isDone()).isFalse();
    startSignal.countDown();

    ReferenceEntry<Object, Object> entry = segment.getEntry(one, hash);
    ReferenceEntry<Object, Object> newEntry = segment.copyEntry(entry, null);
    table.set(index, newEntry);

    @SuppressWarnings("unchecked")
    LoadingValueReference<Object, Object> valueReference =
        (LoadingValueReference) newEntry.getValueReference();
    assertThat(valueReference.futureValue.isDone()).isFalse();
    startSignal.countDown();

                    final Object rawData = resultData.getRawData();
                    if (rawData != null) {
                        @SuppressWarnings("unchecked")
                        final Map<String, Object> responseDataMap = (Map<String, Object>) rawData;
                        mergeResponseData(dataMap, responseDataMap);
                    } else {

    void sendWithRequestVarargsDelegates() throws Exception {
        // Verifies Request<T> overload forwards to the varargs form with a null response
        @SuppressWarnings("unchecked")
        Request<CommonServerMessageBlockResponse> req = mock(Request.class);
        CommonServerMessageBlockResponse resp = mock(CommonServerMessageBlockResponse.class);

        // Stub tree send for varargs

            // A sorted spliterator with no comparator is already using natural order.
            // (We could probably find a way to avoid rawtypes here if we wanted.)
            @SuppressWarnings({"unchecked", "rawtypes"})
            Comparator<? super E> naturalOrder =
                (Comparator<? super E>) Comparator.<Comparable>naturalOrder();
            comparator = naturalOrder;
          }

            // A sorted spliterator with no comparator is already using natural order.
            // (We could probably find a way to avoid rawtypes here if we wanted.)
            @SuppressWarnings({"unchecked", "rawtypes"})
            Comparator<? super E> naturalOrder =
                (Comparator<? super E>) Comparator.<Comparable>naturalOrder();
            comparator = naturalOrder;
          }

          // operations only in weird cases like checking for an EndpointPair<ArrayList> in a
          // Network<LinkedList>.
          @SuppressWarnings("unchecked")
          @Override
          public boolean contains(@Nullable Object obj) {
            if (!(obj instanceof EndpointPair)) {
              return false;
            }