try {
      List<Future<int[]>> futures = newArrayListWithExpectedSize(nTasks);
      for (int i = 0; i < nTasks; i++) {
        futures.add(pool.submit(new MutateTask(multiset, keys)));
      }

      int[] deltas = new int[3];
      for (Future<int[]> future : futures) {
        int[] taskDeltas = future.get();
        for (int i = 0; i < deltas.length; i++) {

import static com.google.common.truth.Truth.assertThat;
import static com.google.common.util.concurrent.Futures.getDone;
import static com.google.common.util.concurrent.Futures.immediateCancelledFuture;
import static com.google.common.util.concurrent.Futures.immediateFailedFuture;
import static com.google.common.util.concurrent.Futures.immediateFuture;
import static com.google.common.util.concurrent.ReflectionFreeAssertThrows.assertThrows;

import java.lang.ref.WeakReference;
import java.net.URLClassLoader;
import java.util.concurrent.CancellationException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeoutException;
import junit.framework.TestCase;

/** Unit tests for {@link Futures#getChecked(Future, Class)}. */
public class FuturesGetCheckedTest extends TestCase {
  // Boring untimed-get tests:

import com.google.common.annotations.J2ktIncompatible;

/**
 * Hidden superclass of {@link Futures} that provides us a place to declare special GWT versions of
 * the {@link Futures#catching(ListenableFuture, Class, com.google.common.base.Function,
 * java.util.concurrent.Executor) Futures.catching} family of methods. Those versions have slightly
 * different signatures.
 */
@GwtCompatible(emulated = true)

      Executor executor) {
    return (FluentFuture<V>) Futures.catching(this, exceptionType, fallback, executor);
  }

  public final FluentFuture<V> catchingAsync(
      Class<Throwable> exceptionType,
      AsyncFunction<? super Throwable, ? extends V> fallback,
      Executor executor) {
    return (FluentFuture<V>) Futures.catchingAsync(this, exceptionType, fallback, executor);
  }

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.util.concurrent.CancellationException;
import java.util.concurrent.Future;
import junit.framework.TestCase;

/** Unit tests for {@link Futures#getUnchecked(Future)}. */
@GwtCompatible(emulated = true)
public class FuturesGetUncheckedTest extends TestCase {
  public void testGetUnchecked_success() {

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.util.concurrent.CancellationException;
import java.util.concurrent.Future;
import junit.framework.TestCase;

/** Unit tests for {@link Futures#getUnchecked(Future)}. */
@GwtCompatible(emulated = true)
public class FuturesGetUncheckedTest extends TestCase {
  public void testGetUnchecked_success() {

    final AtomicLongMap<String> map = AtomicLongMap.create();

    ExecutorService threadPool = Executors.newFixedThreadPool(nThreads);
    ArrayList<Future<Long>> futures = new ArrayList<>();
    for (int i = 0; i < nTasks; i++) {
      futures.add(
          threadPool.submit(
              new Callable<Long>() {
                @Override
                public Long call() {
                  long threadSum = 0;

        // Callableタスク(複数)を実行する
        final ExecutorService executor = Executors.newFixedThreadPool(numTasks);
        try {
            final List<Future<Integer>> futures = executor.invokeAll(tasks);
            for (final Future<Integer> future : futures) {
                future.get();
            }
        } catch (final InterruptedException e) {
            // no thing to do
        } catch (final ExecutionException e) {

 *       Future} is "completed" even if it is cancelled while its underlying work continues on a
 *       thread, an RPC, etc. The {@code Future} is also "completed" if it fails "early" -- for
 *       example, if the deadline expires on a {@code Future} returned from {@link
 *       Futures#withTimeout} while the {@code Future} it wraps continues its underlying work. So