* Future, then a call setException() would likely also overflow.
     *
     * - If the stack overflowed after set()/setValue() stored its result, then a call to
     * setException() will be a no-op because the Future is already done.
     *
     * Both scenarios are bad: The output Future might never complete, or, if it does complete, it

 * share the same [Address] may share a [Connection]. This class implements the policy
 * of which connections to keep open for future use.
 *
 * @constructor Create a new connection pool with tuning parameters appropriate for a single-user
 * application. The tuning parameters in this pool are subject to change in future OkHttp releases.
 * Currently this pool holds up to 5 idle connections which will be evicted after 5 minutes of
 * inactivity.
 */

    /**
     * Contains the most recently submitted {@code Future}, which may be cancelled or updated,
     * always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

      @GuardedBy("lock")
      private Future<@Nullable Void> currentFuture;

      SupplantableFuture(ReentrantLock lock, Future<@Nullable Void> currentFuture) {
        this.lock = lock;

      ListeningExecutorService executorService, Callable<T> task, BlockingQueue<Future<T>> queue) {
    ListenableFuture<T> future = executorService.submit(task);
    future.addListener(() -> queue.add(future), directExecutor());
    return future;
  }

  /**
   * Returns a default thread factory used to create new threads.
   *
   * <p>When running on AppEngine with access to <a

    }

    @Override
    public Future<ProjectSegment> take() throws InterruptedException {
        return null;
    }

    @Override
    public Future<ProjectSegment> poll() {
        return null;
    }

    @Override
    public Future<ProjectSegment> poll(long timeout, TimeUnit unit) throws InterruptedException {
        return null;
    }

    CountDownLatch latch = new CountDownLatch(1);
    SettableFuture<?> future = SettableFuture.create();
    Executor delegate =
        new Executor() {
          @Override
          public void execute(Runnable task) {
            if (future.set(null)) {
              awaitUninterruptibly(latch);
            }
            throw new RejectedExecutionException();

import static com.google.common.util.concurrent.Futures.immediateFuture;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.util.concurrent.ListenableFuture;
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.Map;
import java.util.concurrent.Executor;
import java.util.concurrent.Future;
import java.util.concurrent.atomic.AtomicInteger;

    delegate().execute(command);
  }

  @Override
  public <T extends @Nullable Object> Future<T> submit(Callable<T> task) {
    return delegate().submit(task);
  }

  @Override
  public Future<?> submit(Runnable task) {
    return delegate().submit(task);
  }

  @Override
  public <T extends @Nullable Object> Future<T> submit(
      Runnable task, @ParametricNullness T result) {

+-----+
<project>
 <modelVersion>4.0.0</modelVersion>
 <parent>
   <groupId></groupId>
   <artifactId></artifactId>
   <version></version>
 </parent>
</project>
+-----+

Extending the POM in the future

  In order to anticipate changes in the structure of the POM as new releases of
  maven occur, the maven inheritance model must be pinned against a particular

abstract class AggregateFutureState<OutputT extends @Nullable Object>
    extends AbstractFuture.TrustedFuture<OutputT> {
  // Lazily initialized the first time we see an exception; not released until all the input futures
  // & this future completes. Released when the future releases the reference to the running state
  private @Nullable Set<Throwable> seenExceptions = null;
  private int remaining;

  AggregateFutureState(int remainingFutures) {