herself.

  `Of the mushroom,' said the Caterpillar, just as if she had
asked it aloud; and in another moment it was out of sight.

  Alice remained looking thoughtfully at the mushroom for a
minute, trying to make out which were the two sides of it; and as
it was perfectly round, she found this a very difficult question.
However, at last she stretched her arms round it as far as they
would go, and broke off a bit of the edge with each hand.

      return false;
    }

    // This implementation is patterned after ConcurrentHashMap, but without the locking. The only
    // way for it to return a false negative would be for the target value to jump around in the map
    // such that none of the subsequent iterations observed it, despite the fact that at every point
    // in time it was present somewhere int the map. This becomes increasingly unlikely as

    combiner = null;
    // combiner should be collected even if the future it returns never completes.
    GcFinalization.awaitClear(combinerRef);
  }

  /*
   * TODO(cpovirk): maybe pass around TestFuture instances instead of
   * ListenableFuture instances
   */

  /**
   * A future in {@link TestFutureBatch} that also has a name for debugging purposes and a {@code

herself.

  `Of the mushroom,' said the Caterpillar, just as if she had
asked it aloud; and in another moment it was out of sight.

  Alice remained looking thoughtfully at the mushroom for a
minute, trying to make out which were the two sides of it; and as
it was perfectly round, she found this a very difficult question.
However, at last she stretched her arms round it as far as they
would go, and broke off a bit of the edge with each hand.

    combiner = null;
    // combiner should be collected even if the future it returns never completes.
    GcFinalization.awaitClear(combinerRef);
  }

  /*
   * TODO(cpovirk): maybe pass around TestFuture instances instead of
   * ListenableFuture instances
   */

  /**
   * A future in {@link TestFutureBatch} that also has a name for debugging purposes and a {@code

    assertSame(testEquivalence, map.valueEquivalence);
    assertSame(map.keyStrength.defaultEquivalence(), map.keyEquivalence);
  }

  public void testSetConcurrencyLevel() {
    // round up to the nearest power of two

    checkConcurrencyLevel(1, 1);
    checkConcurrencyLevel(2, 2);
    checkConcurrencyLevel(3, 4);
    checkConcurrencyLevel(4, 4);
    checkConcurrencyLevel(5, 8);

    assertSame(testEquivalence, map.valueEquivalence);
    assertSame(map.keyStrength.defaultEquivalence(), map.keyEquivalence);
  }

  public void testSetConcurrencyLevel() {
    // round up to the nearest power of two

    checkConcurrencyLevel(1, 1);
    checkConcurrencyLevel(2, 2);
    checkConcurrencyLevel(3, 4);
    checkConcurrencyLevel(4, 4);
    checkConcurrencyLevel(5, 8);

      return false;
    }

    // This implementation is patterned after ConcurrentHashMap, but without the locking. The only
    // way for it to return a false negative would be for the target value to jump around in the map
    // such that none of the subsequent iterations observed it, despite the fact that at every point
    // in time it was present somewhere int the map. This becomes increasingly unlikely as

      TreeMap<K, V> newTreeMap(@CheckForNull Comparator<C> comparator) {
    // Ideally, the extra type parameter "C" shouldn't be necessary. It is a
    // work-around of a compiler type inference quirk that prevents the
    // following code from being compiled:
    // Comparator<Class<?>> comparator = null;
    // Map<Class<? extends Throwable>, String> map = newTreeMap(comparator);

     * @param closingExecutor the object will be closed on this executor
     * @return the first argument
     */
    @CanIgnoreReturnValue
    @ParametricNullness
    // TODO(b/163345357): Widen bound to AutoCloseable once we require API Level 19.
    public <C extends @Nullable Object & @Nullable Closeable> C eventuallyClose(
        @ParametricNullness C closeable, Executor closingExecutor) {