final Supplier<T> delegate;

    ThreadSafeSupplier(Supplier<T> delegate) {
      this.delegate = checkNotNull(delegate);
    }

    @Override
    @ParametricNullness
    public T get() {
      synchronized (delegate) {
        return delegate.get();
      }
    }

    @Override
    public String toString() {
      return "Suppliers.synchronizedSupplier(" + delegate + ")";
    }

  }

  class BiMapEntry extends ForwardingMapEntry<K, V> {
    private final Entry<K, V> delegate;

    BiMapEntry(Entry<K, V> delegate) {
      this.delegate = delegate;
    }

    @Override
    protected Entry<K, V> delegate() {
      return delegate;
    }

    @Override
    public V setValue(V value) {
      checkValue(value);

    assertThat(future.setFuture(delegate)).isTrue();
    assertThat(future.cancel(true /* mayInterruptIfRunning */)).isTrue();
    assertCancelled(future, true);
    assertCancelled(delegate, true);
  }

  public void testSetFutureDelegateAlreadySuccessful() throws Exception {
    delegate.set(5);
    assertThat(future.setFuture(delegate)).isTrue();
    assertSuccessful(future, 5);
  }

          @Override
          public NoDelegateToEquals apply(Equals delegate) {
            return new NoDelegateToEquals(delegate);
          }
        };

    private final Equals delegate;

    NoDelegateToEquals(Equals delegate) {
      this.delegate = delegate;
    }

    @Override
    public String toString() {
      return delegate.toString();
    }
  }

    private final TestSortedSetGenerator<E> delegate;

    public SortedSetSubsetTestSetGenerator(
        TestSortedSetGenerator<E> delegate, Bound to, Bound from) {
      this.to = to;
      this.from = from;
      this.delegate = delegate;

      SortedSet<E> emptySet = delegate.create();
      this.comparator = emptySet.comparator();

      SampleElements<E> samples = delegate.samples();

              delegate().incidentEdges(node).iterator(),
              edge -> EndpointPair.of(delegate(), edge.nodeV(), edge.nodeU()));
        }
      };
    }

    @Override
    public int inDegree(N node) {
      return delegate().outDegree(node); // transpose
    }

    @Override
    public int outDegree(N node) {
      return delegate().inDegree(node); // transpose
    }

  public static ListeningExecutorService listeningDecorator(ExecutorService delegate) {
    return (delegate instanceof ListeningExecutorService)
        ? (ListeningExecutorService) delegate
        : (delegate instanceof ScheduledExecutorService)
            ? new ScheduledListeningDecorator((ScheduledExecutorService) delegate)
            : new ListeningDecorator(delegate);
  }

  /**

              delegate().incidentEdges(node).iterator(),
              edge -> EndpointPair.of(delegate(), edge.nodeV(), edge.nodeU()));
        }
      };
    }

    @Override
    public int inDegree(N node) {
      return delegate().outDegree(node); // transpose
    }

    @Override
    public int outDegree(N node) {
      return delegate().inDegree(node); // transpose
    }

    private final TestSortedSetGenerator<E> delegate;

    public SortedSetSubsetTestSetGenerator(
        TestSortedSetGenerator<E> delegate, Bound to, Bound from) {
      this.to = to;
      this.from = from;
      this.delegate = delegate;

      SortedSet<E> emptySet = delegate.create();
      this.comparator = emptySet.comparator();

      SampleElements<E> samples = delegate.samples();

  @Override
  protected abstract Map<K, V> delegate();

  @Override
  public int size() {
    return delegate().size();
  }

  @Override
  public boolean isEmpty() {
    return delegate().isEmpty();
  }

  @CanIgnoreReturnValue
  @Override
  @CheckForNull
  public V remove(@CheckForNull Object key) {
    return delegate().remove(key);
  }

  @Override
  public void clear() {