}

    @Override
    public boolean tryLock() {
      aboutToAcquire(this);
      try {
        return super.tryLock();
      } finally {
        lockStateChanged(this);
      }
    }

    @Override
    public boolean tryLock(long timeout, TimeUnit unit) throws InterruptedException {
      aboutToAcquire(this);
      try {
        return super.tryLock(timeout, unit);
      } finally {

    assertFalse(lockA.tryLock());

    thread.releaseLockAndFinish();
    assertTrue(lockA.tryLock());
  }

  public void testReentrantWriteLock_tryLock() throws Exception {
    LockingThread thread = new LockingThread(writeLockA);
    thread.start();

    thread.waitUntilHoldingLock();
    assertFalse(writeLockA.tryLock());
    assertFalse(readLockA.tryLock());

    thread.releaseLockAndFinish();

    assertFalse(lockA.tryLock());

    thread.releaseLockAndFinish();
    assertTrue(lockA.tryLock());
  }

  public void testReentrantWriteLock_tryLock() throws Exception {
    LockingThread thread = new LockingThread(writeLockA);
    thread.start();

    thread.waitUntilHoldingLock();
    assertFalse(writeLockA.tryLock());
    assertFalse(readLockA.tryLock());

    thread.releaseLockAndFinish();

    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          maybeDrainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    @GuardedBy("this")

      }
    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          drainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    /**

    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          maybeDrainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    @GuardedBy("this")

      }
    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          drainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    /**

    WeakReference<Object> garbage = createGarbage();
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    try {
      assertFalse(writeLock.tryLock());
    } finally {
      readLock.unlock();
    }
  }

  private WeakReference<Object> createGarbage() {
    return new WeakReference<>(new Object());
  }

    WeakReference<Object> garbage = createGarbage();
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    try {
      assertFalse(writeLock.tryLock());
    } finally {
      readLock.unlock();
    }
  }

  private WeakReference<Object> createGarbage() {
    return new WeakReference<>(new Object());
  }

    assertTrue(returnedBeforeTimeout);
    assertTimeNotPassed(stopwatch, LONG_DELAY_MS);
    assertInterrupted();
  }

  // Lock.tryLock() tests
  public void testTryLockTimeoutExceeded() {
    Stopwatch stopwatch = Stopwatch.createStarted();
    Lock lock = new ReentrantLock();
    Thread lockThread = acquireFor(lock, 5, SECONDS);