if (result == null) {
      globalStatsCounter.recordLoadException(stopwatch.elapsed(NANOSECONDS));
      throw new InvalidCacheLoadException(loader + " returned null map from loadAll");
    }

    stopwatch.stop();
    // TODO(fry): batch by segment
    boolean nullsPresent = false;
    for (Entry<K, V> entry : result.entrySet()) {
      K key = entry.getKey();
      V value = entry.getValue();

   *
   * <p><b>Warning:</b> If the function rejects {@code null}, caution is required to make sure the
   * set does not contain {@code null}, because the view cannot stop {@code null} from being added
   * to the set.
   *
   * <p><b>Warning:</b> This method assumes that for any instance {@code k} of key type {@code K},

 * is by declaring that step to be the last step of the pipeline. Nevertheless, we refer to the
 * "value" of a successful step or the "result" (value or exception) of any step.
 *
 * <ol>
 *   <li>A pipeline starts at its leaf step (or steps), which is created from either a callable
 *       block or a {@link ListenableFuture}.

      @Override
      public Integer apply(Integer from) {
        if (++calls > 1) {
          fail();
        }
        throw new MyError();
      }
    };
  }

  // TODO(cpovirk): top-level class?
  static class ExecutorSpy implements Executor {

    Executor delegate;
    boolean wasExecuted;

    public ExecutorSpy(Executor delegate) {
      this.delegate = delegate;
    }

    if (result == null) {
      globalStatsCounter.recordLoadException(stopwatch.elapsed(NANOSECONDS));
      throw new InvalidCacheLoadException(loader + " returned null map from loadAll");
    }

    stopwatch.stop();
    // TODO(fry): batch by segment
    boolean nullsPresent = false;
    for (Entry<K, V> entry : result.entrySet()) {
      K key = entry.getKey();
      V value = entry.getValue();