* {@link #shutDown} and also a {@link #runOneIteration} method that will be executed periodically.
 *
 * <p>This class uses the {@link ScheduledExecutorService} returned from {@link #executor} to run
 * the {@link #startUp} and {@link #shutDown} methods and also uses that service to schedule the
 * {@link #runOneIteration} that will be executed periodically as specified by its {@link

      final Runnable runnable;
      final Executor executor;

      RunnableExecutorPair(Runnable runnable, Executor executor) {
        this.runnable = runnable;
        this.executor = executor;
      }

      void execute() {
        try {
          executor.execute(runnable);
        } catch (RuntimeException e) {
          log.log(
              Level.SEVERE,
              "RuntimeException while executing runnable "

              }
            }
          };
      executor.execute(errorTask);
      service.execute(barrierTask); // submit directly to the service
      // the barrier task runs after the error task so we know that the error has been observed by
      // SequentialExecutor by the time the barrier is satisfied
      barrier.await(1, TimeUnit.SECONDS);
      executor.execute(barrierTask);

    }

    eventListener.canceled(this)
  }

  override fun isCanceled(): Boolean = canceled

  override fun execute(): Response {
    check(executed.compareAndSet(false, true)) { "Already Executed" }

    timeout.enter()
    callStart()
    try {
      client.dispatcher.executed(this)
      return getResponseWithInterceptorChain()
    } finally {
      client.dispatcher.finished(this)
    }
  }

   */
  public static <V extends @Nullable Object> ListenableFuture<V> listenInPoolThread(
      Future<V> future, Executor executor) {
    checkNotNull(executor);
    if (future instanceof ListenableFuture) {
      return (ListenableFuture<V>) future;
    }
    return new ListenableFutureAdapter<>(future, executor);
  }

  /**
   * An adapter to turn a {@link Future} into a {@link ListenableFuture}. This will wait on the

              }
            }
          };
      executor.execute(errorTask);
      service.execute(barrierTask); // submit directly to the service
      // the barrier task runs after the error task so we know that the error has been observed by
      // SequentialExecutor by the time the barrier is satisfied
      barrier.await(1, TimeUnit.SECONDS);
      executor.execute(barrierTask);

    ExecutorService executor = newDirectExecutorService();
    assertEquals(ImmutableList.of(), executor.shutdownNow());
    assertTrue(executor.isShutdown());
  }

  public void testExecuteAfterShutdown() {
    ExecutorService executor = newDirectExecutorService();
    executor.shutdown();
    assertThrows(RejectedExecutionException.class, () -> executor.execute(EMPTY_RUNNABLE));
  }

    }
  }

  val logger = Logger.getLogger("TaskFaker." + instance++)

  /** Though this executor service may hold many threads, they are not executed concurrently. */
  private val tasksExecutor = Executors.newCachedThreadPool(threadFactory("TaskFaker"))

  /**
   * True if this task faker has ever had multiple tasks scheduled to run concurrently. Guarded by

import java.util.Deque;
import java.util.concurrent.Executor;
import java.util.concurrent.RejectedExecutionException;
import java.util.logging.Level;
import javax.annotation.CheckForNull;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *

    ExecutorService executor = newDirectExecutorService();
    assertEquals(ImmutableList.of(), executor.shutdownNow());
    assertTrue(executor.isShutdown());
  }

  public void testExecuteAfterShutdown() {
    ExecutorService executor = newDirectExecutorService();
    executor.shutdown();
    assertThrows(RejectedExecutionException.class, () -> executor.execute(EMPTY_RUNNABLE));
  }