*
   * <p>When passed a key that is present in the map, {@code asMap().get(Object)} has the same
   * behavior as {@link #get}, returning a live collection. When passed a key that is not present,
   * however, {@code asMap().get(Object)} returns {@code null} instead of an empty collection.
   *

   */
  @CanIgnoreReturnValue // TODO(b/27479612): consider removing this?
  V get(K key) throws ExecutionException;

  /**
   * Returns the value associated with {@code key} in this cache, first loading that value if
   * necessary. No observable state associated with this cache is modified until loading completes.
   * Unlike {@link #get}, this method does not throw a checked exception, and thus should only be

    }
    return elements.get(0);
  }

  @Override
  public E last() {
    if (isEmpty()) {
      throw new NoSuchElementException();
    }
    return elements.get(size() - 1);
  }

  @Override
  @CheckForNull
  public E lower(E element) {
    int index = headIndex(element, false) - 1;
    return (index == -1) ? null : elements.get(index);
  }

  @Override

    AsyncCallable<String> asyncCallable =
        Callables.asAsyncCallable(callable, MoreExecutors.newDirectExecutorService());

    ListenableFuture<String> future = asyncCallable.call();
    assertSame(expected, future.get());
  }

  @J2ktIncompatible
  @GwtIncompatible
  public void testAsAsyncCallable_exception() throws Exception {
    final Exception expected = new IllegalArgumentException();
    Callable<String> callable =

        assertThat(graph.removeNode(nodeList.get(i))).isTrue();
      }

      assertThat(graph.nodes()).hasSize(NUM_NODES - numNodesToRemove);
      // Number of edges remaining is unknown (node's incident edges have been removed).
      AbstractGraphTest.validateGraph(graph);

      for (int i = numNodesToRemove; i < NUM_NODES; ++i) {
        assertThat(graph.removeNode(nodeList.get(i))).isTrue();
      }

    return (Optional<T>) INSTANCE;
  }

  private Absent() {}

  @Override
  public boolean isPresent() {
    return false;
  }

  @Override
  public T get() {
    throw new IllegalStateException("Optional.get() cannot be called on an absent value");
  }

  @Override
  public T or(T defaultValue) {
    return checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
  }

    return (Optional<T>) INSTANCE;
  }

  private Absent() {}

  @Override
  public boolean isPresent() {
    return false;
  }

  @Override
  public T get() {
    throw new IllegalStateException("Optional.get() cannot be called on an absent value");
  }

  @Override
  public T or(T defaultValue) {
    return checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
  }

  }

  /**
   * Wrapper for {@link Map#get(Object)} that forces the caller to pass in a key of the same type as
   * the map. Besides being slightly shorter than code that uses {@link #getMap()}, it also ensures
   * that callers don't pass an {@link Entry} by mistake.
   */
  protected V get(K key) {
    return getMap().get(key);
  }

  protected final K k0() {
    return e0().getKey();
  }

    assertTrue(task.isDone());
    assertTrue(task.isCancelled());
    assertTrue(task.wasInterrupted());
    try {
      task.get();
      fail();
    } catch (CancellationException expected) {
    }
    exitLatch.await();
    assertTrue(interruptedExceptionThrown.get());
  }

  @J2ktIncompatible
  @GwtIncompatible // blocking wait
  public void testRunIdempotency() throws Exception {

    assertEqualIgnoringOrder(values, multimap().get(key));

    if (!values.isEmpty()) {
      assertEqualIgnoringOrder(values, multimap().asMap().get(key));
      assertFalse(multimap().isEmpty());
    } else {
      assertNull(multimap().asMap().get(key));
    }

    assertEquals(values.size(), multimap().get(key).size());

    assertEquals(values.size() > 0, multimap().containsKey(key));