AtomicHelper helper;
    Throwable thrownUnsafeFailure = null;
    Throwable thrownAtomicReferenceFieldUpdaterFailure = null;

    try {
      helper = new UnsafeAtomicHelper();
    } catch (Exception | Error unsafeFailure) { // sneaky checked exception
      thrownUnsafeFailure = unsafeFailure;
      // catch absolutely everything and fall through to our 'SafeAtomicHelper'

   * </ol>
   *
   * <p>{@code RuntimeException}s thrown by tasks are simply logged and the executor keeps trucking.
   * If an {@code Error} is thrown, the error will propagate and execution will stop until the next
   * time a task is submitted.
   *
   * <p>When an {@code Error} is thrown by an executed task, previously submitted tasks may never

    } catch (Exception e) { // sneaky checked exception
      // Log it and keep going -- bad runnable and/or executor. Don't punish the other runnables if
      // we're given a bad one. We only catch Exception because we want Errors to propagate up.
      log.get()
          .log(
              Level.SEVERE,
              "RuntimeException while executing runnable "
                  + runnable
                  + " with executor "

        return (Comparator) Ordering.natural().reverse();
      } else {
        return reverse(forwardComparator);
      }
    }

    // If we inline this, we get a javac error.
    private static <T extends @Nullable Object> Ordering<T> reverse(Comparator<T> forward) {
      return Ordering.from(forward).reverse();
    }

    @Override
    @ParametricNullness

          forwardCmp = (Comparator) Ordering.natural();
        }
        result = comparator = reverse(forwardCmp);
      }
      return result;
    }

    // If we inline this, we get a javac error.
    private static <T extends @Nullable Object> Ordering<T> reverse(Comparator<T> forward) {
      return Ordering.from(forward).reverse();
    }

    @Override
    @ParametricNullness

 * used; or if the class exposes a public parameter-less constructor then it will be "new"d and
 * returned.
 *
 * <p>All default instances returned by {@link #get} are generics-safe. Clients won't get type
 * errors for using {@code get(Comparator.class)} as a {@code Comparator<Foo>}, for example.
 * Immutable empty instances are returned for collection types; {@code ""} for string; {@code 0} for

 * used; or if the class exposes a public parameter-less constructor then it will be "new"d and
 * returned.
 *
 * <p>All default instances returned by {@link #get} are generics-safe. Clients won't get type
 * errors for using {@code get(Comparator.class)} as a {@code Comparator<Foo>}, for example.
 * Immutable empty instances are returned for collection types; {@code ""} for string; {@code 0} for

  @SuppressWarnings({"AndroidJdkLibsChecker", "Java7ApiChecker"})
  @IgnoreJRERequirement // helper for toImmutableSortedMultiset
  /*
   * If we make these calls inline inside toImmutableSortedMultiset, we get an Animal Sniffer error,
   * despite the @IgnoreJRERequirement annotation there. My assumption is that, because javac
   * generates a synthetic method for the body of the lambda, the actual method calls that Animal