return 25;
            }
          });

  @Override
  protected void setUp() throws Exception {
    super.setUp();

    exec = newCachedThreadPool();

    task.addListener(
        new Runnable() {
          @Override
          public void run() {
            listenerLatch.countDown();
          }
        },
        directExecutor());
  }

  @Override

      this.adapterExecutor = checkNotNull(adapterExecutor);
    }

    @Override
    protected Future<V> delegate() {
      return delegate;
    }

    @Override
    public void addListener(Runnable listener, Executor exec) {
      executionList.add(listener, exec);

      // When a listener is first added, we run a task that will wait for the delegate to finish,
      // and when it is done will run the listeners.

  @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
  static void awaitWaiting(Thread t) {
    while (true) {
      Thread.State state = t.getState();
      switch (state) {
        case RUNNABLE:
        case BLOCKED:
          Thread.yield();
          break;
        case WAITING:
          return;
        default:
          throw new AssertionError("unexpected state: " + state);
      }
    }

   * this method to use a custom {@link Executor}, which may configure its worker thread with a
   * specific name, thread group or priority. The returned executor's {@link
   * Executor#execute(Runnable) execute()} method is called when this service is started, and should
   * return promptly.
   *
   * <p>The default implementation returns a new {@link Executor} that sets the name of its threads

        };
    addCallback(f, callback, directExecutor());
  }

  private class CountingSameThreadExecutor implements Executor {
    int runCount = 0;

    @Override
    public void execute(Runnable command) {
      command.run();
      runCount++;
    }
  }

  private final class MockCallback implements FutureCallback<String> {
    @Nullable private String value = null;

    assertTrue(ArbitraryInstances.get(ConcurrentMap.class).isEmpty());
    assertTrue(ArbitraryInstances.get(ConcurrentNavigableMap.class).isEmpty());
    ArbitraryInstances.get(Executor.class).execute(ArbitraryInstances.get(Runnable.class));
    assertNotNull(ArbitraryInstances.get(ThreadFactory.class));
    assertFreshInstanceReturned(
        BlockingQueue.class,
        BlockingDeque.class,
        PriorityBlockingQueue.class,

    }

    @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
    Interruptenator(Thread interruptee, AtomicBoolean shutdown) {
      super(
          new Runnable() {
            @Override
            public void run() {
              while (!shutdown.get()) {
                interruptee.interrupt();
                Thread.yield();
              }
            }

    }

    @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
    Interruptenator(Thread interruptee, AtomicBoolean shutdown) {
      super(
          new Runnable() {
            @Override
            public void run() {
              while (!shutdown.get()) {
                interruptee.interrupt();
                Thread.yield();
              }
            }

          InetAddress.getAllByName(hostname).toList()
    })
    .build()
```

SAM conversion impacts these APIs:

 * Authenticator
 * Dispatcher.setIdleCallback(Runnable)
 * Dns
 * EventListener.Factory
 * HttpLoggingInterceptor.Logger
 * LoggingEventListener.Factory
 * OkHttpClient.Builder.hostnameVerifier(HostnameVerifier)

   * this method to use a custom {@link Executor}, which may configure its worker thread with a
   * specific name, thread group or priority. The returned executor's {@link
   * Executor#execute(Runnable) execute()} method is called when this service is started, and should
   * return promptly.
   *
   * <p>The default implementation returns a new {@link Executor} that sets the name of its threads