return instance;
    }

    /**
     * Starts the process.
     */
    public synchronized void start() {
        if (thread == null) {
            thread = new Thread(this, "CoreLib-TimeoutManager");
            thread.setDaemon(true);
            thread.start();
            if (logger.isDebugEnabled()) {
                logger.debug("TimeoutManager started.");
            }
        }
    }

    Stopwatch stopwatch = Stopwatch.createStarted();
    Thread thread = new Thread(new JoinTarget(15));
    thread.start();
    thread.join();
    assertFalse(thread.isAlive());

    joinUninterruptibly(thread);
    joinUninterruptibly(thread, 0, MILLISECONDS);
    joinUninterruptibly(thread, -42, MILLISECONDS);
    joinUninterruptibly(thread, LONG_DELAY_MS, MILLISECONDS);

 * thread) the subscriber is actually called when an event is dispatched to it.
 *
 * @author Colin Decker
 */
abstract class Dispatcher {

  /**
   * Returns a dispatcher that queues events that are posted reentrantly on a thread that is already
   * dispatching an event, guaranteeing that all events posted on a single thread are dispatched to

            });
    assertFalse(task.isDone());
    Thread thread =
        new Thread(
            new Runnable() {
              @Override
              public void run() {
                try {
                  task.run();
                } finally {
                  exitLatch.countDown();
                }
              }
            });
    thread.start();
    enterLatch.await();

    }
  }

  /** Wait for the given thread to reach the {@link State#TIMED_WAITING} thread state. */
  @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
  void awaitTimedWaiting(Thread thread) {
    while (true) {
      switch (thread.getState()) {
        case BLOCKED:
        case NEW:
        case RUNNABLE:
        case WAITING:
          Thread.yield();
          break;

   * <p>On the other hand, if a signalled thread wakes up to discover that its guard is still not
   * satisfied, it does *not* need to call this method before returning to wait. This can only
   * happen due to spurious wakeup (ignorable) or another thread acquiring the lock before the
   * current thread can and returning the guard to the unsatisfied state. In the latter case the

     * exception. But there's another race: If the first thread fails with an exception and a second
     * thread immediately fails with the same exception:
     *
     * Thread1: calls setException(), which returns true, context switch before it can CAS
     * seenExceptionsField to its exception
     *
     * Thread2: calls setException(), which returns false, CASes seenExceptionsField to its

          public @Nullable Void call() throws Exception {
            assertEquals(Thread.currentThread().getName(), newName.get());
            return null;
          }
        };
    Callables.threadRenaming(callable, newName).call();
    assertEquals(oldName, Thread.currentThread().getName());
  }

  @J2ktIncompatible
  @GwtIncompatible // threads
  public void testRenaming_exceptionalReturn() throws Exception {

      // unpark even though the thread has already removed itself from the list. But even if we did
      // use a CAS, that race would still exist (it would just be ever so slightly smaller).
      Thread w = thread;
      if (w != null) {
        thread = null;
        LockSupport.unpark(w);
      }
    }
  }

  /*

      // unpark even though the thread has already removed itself from the list. But even if we did
      // use a CAS, that race would still exist (it would just be ever so slightly smaller).
      Thread w = thread;
      if (w != null) {
        thread = null;
        LockSupport.unpark(w);
      }
    }
  }

  /*