@ElementTypesAreNonnullByDefault
public interface FutureCallback<V extends @Nullable Object> {
  /** Invoked with the result of the {@code Future} computation when it is successful. */
  void onSuccess(@ParametricNullness V result);

  /**
   * Invoked when a {@code Future} computation fails or is canceled.
   *
   * <p>If the future's {@link Future#get() get} method throws an {@link ExecutionException}, then

  public void testScheduleRunnable() throws Exception {
    Runnable command = () -> {};

    ListenableScheduledFuture<?> future = executorService.schedule(command, Duration.ofSeconds(12));

    assertThat(future.get()).isEqualTo("schedule");
    assertThat(recordedCommand).isSameInstanceAs(command);
    assertThat(recordedTimeUnit).isEqualTo(TimeUnit.NANOSECONDS);

    }
  }

  private enum Result {
    SUCCESS(immediateFuture(new Object())),
    FAILURE(immediateFailedFuture(new Exception()));

    final Future<Object> future;

    Result(Future<Object> result) {
      this.future = result;
    }
  }

  private enum ExceptionType {
    CHECKED(IOException.class),
    UNCHECKED(RuntimeException.class);

import static com.google.common.util.concurrent.FuturesGetCheckedInputs.FAILED_FUTURE_ERROR;
import static com.google.common.util.concurrent.FuturesGetCheckedInputs.FAILED_FUTURE_OTHER_THROWABLE;
import static com.google.common.util.concurrent.FuturesGetCheckedInputs.FAILED_FUTURE_UNCHECKED_EXCEPTION;
import static com.google.common.util.concurrent.FuturesGetCheckedInputs.OTHER_THROWABLE;

          }

          @Override
          public void onFailure(Throwable t) {
            failureCalls[0]++;
          }
        };
    addCallback(future, callback, directExecutor());
    future.set(result);
    assertEquals(result, future.get());
    assertThat(successCalls[0]).isEqualTo(1);
    assertThat(failureCalls[0]).isEqualTo(0);
  }

  public void testOnSuccessThrowsError() throws Exception {

      Class<X> exceptionType,
      Function<? super X, ? extends V> fallback,
      Executor executor) {
    CatchingFuture<V, X> future = new CatchingFuture<>(input, exceptionType, fallback);
    input.addListener(future, rejectionPropagatingExecutor(executor, future));
    return future;
  }

  static <X extends Throwable, V extends @Nullable Object> ListenableFuture<V> create(
      ListenableFuture<? extends V> input,

  static final Future<String> FAILED_FUTURE_OTHER_THROWABLE =
      immediateFailedFuture(OTHER_THROWABLE);
  static final Error ERROR = new Error("mymessage");
  static final Future<String> FAILED_FUTURE_ERROR = immediateFailedFuture(ERROR);
  static final Future<String> RUNTIME_EXCEPTION_FUTURE =
      UncheckedThrowingFuture.throwingRuntimeException(RUNTIME_EXCEPTION);

    SettableFuture<String> future = SettableFuture.create();
    FutureTask<Boolean> interruptReporter = untimedInterruptReporter(future, false);

    runNInterruptsTest(times, future, interruptReporter);
  }

  private static void runTimedInterruptsTest(int times)
      throws InterruptedException, ExecutionException, TimeoutException {
    SettableFuture<String> future = SettableFuture.create();

  }

  /**
   * Retrieves the result of a {@code Future} known to be done but uses the {@code get(long,
   * TimeUnit)} overload in order to test that method.
   */
  static <V> V getDoneFromTimeoutOverload(Future<V> future) throws ExecutionException {
    checkState(future.isDone(), "Future was expected to be done: %s", future);
    try {
      return getUninterruptibly(future, 0, SECONDS);
    } catch (TimeoutException e) {

            return i;
          }
        };

    List<Future<Integer>> futures = executor.invokeAll(Collections.nCopies(10, incrementTask));

    for (int i = 0; i < 10; i++) {
      Future<Integer> future = futures.get(i);
      assertTrue("Task should have been run before being returned", future.isDone());
      assertEquals(i, future.get().intValue());
    }