assertTrue(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    stopwatch.sleepMillis(100);
    assertFalse(limiter.tryAcquire(0, SECONDS));
  }

  public void testTryAcquire_someWaitAllowed() {
    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);
    assertTrue(limiter.tryAcquire(0, SECONDS));

   */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  public boolean tryAcquire(long timeout, TimeUnit unit) {
    return tryAcquire(1, timeout, unit);
  }

  /**
   * Acquires permits from this {@link RateLimiter} if it can be acquired immediately without delay.
   *
   * <p>This method is equivalent to {@code tryAcquire(permits, 0, anyUnit)}.
   *
   * @param permits the number of permits to acquire

    assertTrue(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    assertFalse(limiter.tryAcquire(0, SECONDS));
    stopwatch.sleepMillis(100);
    assertFalse(limiter.tryAcquire(0, SECONDS));
  }

  public void testTryAcquire_someWaitAllowed() {
    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);
    assertTrue(limiter.tryAcquire(0, SECONDS));

        }
      }
    } finally {
      if (interrupted) {
        Thread.currentThread().interrupt();
      }
    }
  }

  /**
   * Invokes {@code semaphore.}{@link Semaphore#tryAcquire(int, long, TimeUnit) tryAcquire(1,
   * timeout, unit)} uninterruptibly.
   *
   * @since 18.0
   */
  @J2ktIncompatible
  @GwtIncompatible // concurrency
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration

    assertInterrupted();
  }

  public void testSleepMultiInterrupt() {
    repeatedlyInterruptTestThread(10, tearDownStack);
    sleepSuccessfully(100);
    assertInterrupted();
  }

  // Semaphore.tryAcquire() tests
  public void testTryAcquireWithNoWait() {
    Stopwatch stopwatch = Stopwatch.createStarted();
    Semaphore semaphore = new Semaphore(99);
    assertTrue(tryAcquireUninterruptibly(semaphore, 0, MILLISECONDS));

    assertInterrupted();
  }

  public void testSleepMultiInterrupt() {
    repeatedlyInterruptTestThread(10, tearDownStack);
    sleepSuccessfully(100);
    assertInterrupted();
  }

  // Semaphore.tryAcquire() tests
  public void testTryAcquireWithNoWait() {
    Stopwatch stopwatch = Stopwatch.createStarted();
    Semaphore semaphore = new Semaphore(99);
    assertTrue(tryAcquireUninterruptibly(semaphore, 0, MILLISECONDS));

    Field sepFrqUserFinalizedF = sepFrqUserC.getField("finalized");
    Semaphore finalizeCount = (Semaphore) sepFrqUserFinalizedF.get(null);
    boolean finalized = finalizeCount.tryAcquire(5, TimeUnit.SECONDS);
    assertTrue(finalized);

    Field sepFrqUserFrqF = sepFrqUserC.getField("frq");
    Closeable frq = (Closeable) sepFrqUserFrqF.get(null);
    frq.close();

   * This has important consequences: it means that the RateLimiter doesn't remember the time of the
   * _last_ request, but it remembers the (expected) time of the _next_ request. This also enables
   * us to tell immediately (see tryAcquire(timeout)) whether a particular timeout is enough to get
   * us to the point of the next scheduling time, since we always maintain that. And what we mean by

    Field sepFrqUserFinalizedF = sepFrqUserC.getField("finalized");
    Semaphore finalizeCount = (Semaphore) sepFrqUserFinalizedF.get(null);
    boolean finalized = finalizeCount.tryAcquire(5, TimeUnit.SECONDS);
    assertTrue(finalized);

    Field sepFrqUserFrqF = sepFrqUserC.getField("frq");
    Closeable frq = (Closeable) sepFrqUserFrqF.get(null);
    frq.close();

    } catch (Throwable t) {
      threadUnexpectedException(t);
    }
  }

  public void await(Semaphore semaphore) {
    try {
      assertTrue(semaphore.tryAcquire(LONG_DELAY_MS, MILLISECONDS));
    } catch (Throwable t) {
      threadUnexpectedException(t);
    }
  }

  //     /**
  //      * Spin-waits up to LONG_DELAY_MS until flag becomes true.
  //      */