* @author Ben Yu
 * @since 13.0
 */
@ElementTypesAreNonnullByDefault
public final class MutableTypeToInstanceMap<B extends @Nullable Object>
    extends ForwardingMap<TypeToken<? extends @NonNull B>, B> implements TypeToInstanceMap<B> {

  private final Map<TypeToken<? extends @NonNull B>, B> backingMap = Maps.newHashMap();

  @Override
  @CheckForNull
  public <T extends @NonNull B> T getInstance(Class<T> type) {

 * @author Ben Yu
 * @since 13.0
 */
@ElementTypesAreNonnullByDefault
public final class MutableTypeToInstanceMap<B extends @Nullable Object>
    extends ForwardingMap<TypeToken<? extends @NonNull B>, B> implements TypeToInstanceMap<B> {

  private final Map<TypeToken<? extends @NonNull B>, B> backingMap = Maps.newHashMap();

  @Override
  @CheckForNull
  public <T extends @NonNull B> T getInstance(Class<T> type) {

                CollectionSize.ANY,
                MapFeature.ALLOWS_ANY_NULL_QUERIES)
            .createTestSuite());

    return suite;
  }

  private TypeToInstanceMap<Object> map;

  @Override
  protected void setUp() throws Exception {
    map = new MutableTypeToInstanceMap<>();
  }

  public void testPutThrows() {
    assertThrows(