/** Constructor for use by subclasses. */
  protected ForwardingListenableFuture() {}

  @Override
  protected abstract ListenableFuture<? extends V> delegate();

  @Override
  public void addListener(Runnable listener, Executor exec) {
    delegate().addListener(listener, exec);
  }

  // TODO(cpovirk): Use standard Javadoc form for SimpleForwarding* class and constructor
  /**

        if (isEmpty.test(value)) {
            logError(element, "is empty");
        }
    }

    private <T> void validateNonNull(String element, T value, Runnable validator) {
        if (value == null) {
            logError(element, "is missing");
        } else {
            validator.run();
        }
    }

  private Thread executionThread;
  private Throwable thrownByExecutionThread;
  private final Executor exceptionCatchingExecutor =
      new Executor() {
        @Override
        public void execute(Runnable command) {
          executionThread = new Thread(command);
          executionThread.setUncaughtExceptionHandler(
              (thread, throwable) -> thrownByExecutionThread = throwable);
          executionThread.start();

  private static Test testsForSetUpTearDown() {
    AtomicBoolean setUpRan = new AtomicBoolean();
    Runnable setUp =
        () ->
            assertFalse("previous tearDown should have run before setUp", setUpRan.getAndSet(true));
    Runnable tearDown = () -> assertTrue("setUp should have run", setUpRan.getAndSet(false));
    return MapTestSuiteBuilder.using(new CheckSetUpHashMapGenerator(setUpRan))

        public String[] getPermissions() {
            return permissions;
        }
    }

    private static void assertThrows(final Class<? extends Throwable> expectedType, final Runnable runnable) {
        try {
            runnable.run();
            throw new AssertionError("Expected " + expectedType.getSimpleName() + " to be thrown");
        } catch (final Throwable t) {
            if (!expectedType.isInstance(t)) {

 * collected, and this class can detect when the main class loader has been garbage collected and
 * stop itself.
 */
public class Finalizer implements Runnable {

  private static final Logger logger = Logger.getLogger(Finalizer.class.getName());

  /**
   * Starts the Finalizer thread. FinalizableReferenceQueue calls this method reflectively.
   *

   * This means that if you are doing synchronous calls the network layer will not truly be idle
   * until every returned [Response] has been closed.
   */
  @get:Synchronized
  @set:Synchronized
  var idleCallback: Runnable? = null

  private var executorServiceOrNull: ExecutorService? = null

  @get:JvmName("executorService")
  @get:Synchronized
  val executorService: ExecutorService
    get() {

  private static Test testsForSetUpTearDown() {
    AtomicBoolean setUpRan = new AtomicBoolean();
    Runnable setUp =
        () ->
            assertFalse("previous tearDown should have run before setUp", setUpRan.getAndSet(true));
    Runnable tearDown = () -> assertTrue("setUp should have run", setUpRan.getAndSet(false));
    return MapTestSuiteBuilder.using(new CheckSetUpHashMapGenerator(setUpRan))

  @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.fileSuffix = fileSuffix;

        initializeCleanupMonitoring();
    }

    private void initializeCleanupMonitoring() {
        callerInfo = new NullPointerException().getStackTrace()[2];

        Runnable warning = this::maybeWarnAboutCleanUp;

        cleanupWarning = new Thread(warning);

        Runtime.getRuntime().addShutdownHook(cleanupWarning);
    }

    private void maybeWarnAboutCleanUp() {