future2 = null;

    /*
     * Futures should be collected even if combiner never runs. This is kind of a silly test, since
     * the combiner is almost certain to hold its own reference to the futures, and a real app would
     * hold a reference to the executor and thus to the combiner. What we really care about is that
     * the futures are released once the combiner is done running. But we happen to provide this

    future2 = null;

    /*
     * Futures should be collected even if combiner never runs. This is kind of a silly test, since
     * the combiner is almost certain to hold its own reference to the futures, and a real app would
     * hold a reference to the executor and thus to the combiner. What we really care about is that
     * the futures are released once the combiner is done running. But we happen to provide this

      Map<? extends K, ? extends V> map) {
    return new HashMap<>(map);
  }

  /**
   * Creates a {@code HashMap} instance, with a high enough "initial capacity" that it <i>should</i>
   * hold {@code expectedSize} elements without growth. This behavior cannot be broadly guaranteed,
   * but it is observed to be true for OpenJDK 1.7. It also can't be guaranteed that the method