}

  /**
   * Must be called at the end of each subclass's constructor. This method performs the "real"
   * initialization; we can't put this in the constructor because, in the case where futures are
   * already complete, we would not initialize the subclass before calling {@link
   * #collectValueFromNonCancelledFuture}. As this is called after the subclass is constructed,

        pendingDescription = pendingToString();
      } catch (RuntimeException e) {
        // Don't call getMessage or toString() on the exception, in case the exception thrown by the
        // subclass is implemented with bugs similar to the subclass.
        pendingDescription = "Exception thrown from implementation: " + e.getClass();
      }
      // The future may complete during or before the call to getPendingToString, so we use null

    }
  }

  /*
   * TODO(cpovirk): surely we can find a less ugly solution than a class that accepts 3 parameters,
   * exposes as many getters, does work in the constructor, and has both a superclass and a subclass
   */
  public static class SortedMapSubmapTestMapGenerator<
          K extends @Nullable Object, V extends @Nullable Object>
      extends ForwardingTestMapGenerator<K, V> implements TestSortedMapGenerator<K, V> {

    private static ClassOwnership detectJvmBehavior() {
      class LocalClass<T> {}
      Class<?> subclass = new LocalClass<String>() {}.getClass();
      // requireNonNull is safe because we're examining a type that's known to have a superclass.
      ParameterizedType parameterizedType =
          requireNonNull((ParameterizedType) subclass.getGenericSuperclass());
      for (ClassOwnership behavior : ClassOwnership.values()) {

    } catch (NullPointerException expected) {
    }

    assertThat(future.isDone()).isFalse();
    assertThat(future.set(1)).isTrue();
    assertSuccessful(future, 1);
  }

  /** Concrete subclass for testing. */
  private static class TestedFuture<V> extends AbstractFuture<V> {
    private static <V> TestedFuture<V> create() {
      return new TestedFuture<V>();
    }
  }

    assertFalse(isInteger.apply(2.0f));
    assertFalse(isInteger.apply(""));
    assertFalse(isInteger.apply(null));
  }

  @GwtIncompatible // Predicates.instanceOf
  public void testIsInstanceOf_subclass() {
    Predicate<@Nullable Object> isNumber = Predicates.instanceOf(Number.class);

    assertTrue(isNumber.apply(1));
    assertTrue(isNumber.apply(2.0f));
    assertFalse(isNumber.apply(""));

    /*
     * requireNonNull is not safe: Joiner.on(...).join(somethingThatContainsNull) will indeed throw.
     * However, Joiner.on(...).useForNull(...).join(somethingThatContainsNull) *is* safe -- because
     * it returns a subclass of Joiner that overrides this method to tolerate null inputs.
     *
     * Unfortunately, we don't distinguish between these two cases in our public API: Joiner.on(...)

        }

        return request;
    }

    // layer the creation of a project builder configuration with a request, but this will need to be
    // a Maven subclass because we don't want to couple maven to the project builder which we need to
    // separate.
    protected MavenSession createMavenSession(File pom) throws Exception {
        return createMavenSession(pom, new Properties());

   * elements and to build again.
   *
   * @since 2.0
   */
  public static class Builder<E> extends ImmutableCollection.Builder<E> {
    /*
     * `impl` is null only for instances of the subclass, ImmutableSortedSet.Builder. That subclass
     * overrides all the methods that access it here. Thus, all the methods here can safely assume
     * that this field is non-null.
     */
    @CheckForNull private SetBuilderImpl<E> impl;

    } catch (NullPointerException expected) {
    }

    assertThat(future.isDone()).isFalse();
    assertThat(future.set(1)).isTrue();
    assertSuccessful(future, 1);
  }

  /** Concrete subclass for testing. */
  private static class TestedFuture<V> extends AbstractFuture<V> {
    private static <V> TestedFuture<V> create() {
      return new TestedFuture<V>();
    }
  }