this.lock = new ReentrantLock(fair);
  }

  /** Enters this monitor. Blocks indefinitely. */
  public void enter() {
    lock.lock();
  }

  /**
   * Enters this monitor. Blocks at most the given time.
   *
   * @return whether the monitor was entered
   */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  public boolean enter(long time, TimeUnit unit) {

    verifyOccupiedMethodsInAnotherThread(monitor, false, false, 0);
    monitor.enter();
    try {
      verifyOccupiedMethodsInCurrentThread(monitor, true, true, 1);
      verifyOccupiedMethodsInAnotherThread(monitor, true, false, 0);
      monitor.enter();
      try {
        verifyOccupiedMethodsInCurrentThread(monitor, true, true, 2);

    verifyOccupiedMethodsInAnotherThread(monitor, false, false, 0);
    monitor.enter();
    try {
      verifyOccupiedMethodsInCurrentThread(monitor, true, true, 1);
      verifyOccupiedMethodsInAnotherThread(monitor, true, false, 0);
      monitor.enter();
      try {
        verifyOccupiedMethodsInCurrentThread(monitor, true, true, 2);

    }

    /**
     * Attempts to start the timer immediately prior to the service being started via {@link
     * Service#startAsync()}.
     */
    void tryStartTiming(Service service) {
      monitor.enter();
      try {
        Stopwatch stopwatch = startupTimers.get(service);
        if (stopwatch == null) {
          startupTimers.put(service, Stopwatch.createStarted());
        }
      } finally {

      afe.initCause(ie);
      throw afe;
    }
  }

  /**
   * Spin-waits up to the specified number of milliseconds for the given thread to enter a wait
   * state: BLOCKED, WAITING, or TIMED_WAITING.
   */
  void waitForThreadToEnterWaitState(Thread thread, long timeoutMillis) {
    long startTime = System.nanoTime();
    for (; ; ) {

      afe.initCause(ie);
      throw afe;
    }
  }

  /**
   * Spin-waits up to the specified number of milliseconds for the given thread to enter a wait
   * state: BLOCKED, WAITING, or TIMED_WAITING.
   */
  void waitForThreadToEnterWaitState(Thread thread, long timeoutMillis) {
    long startTime = System.nanoTime();
    for (; ; ) {

      } catch (ClassNotFoundException runningUnderAndroidOrJava8) {
        /*
         * I'm not sure that we could actually get here for *Android*: I would expect us to enter
         * the POSIX code path instead. And if we tried this code path, we'd have trouble unless we
         * were running under a new enough version of Android to support NIO.
         *

   *       channel have their own file descriptors. Generally this only happens when both channels
   *       are files or sockets. This performs zero copies - the bytes never enter userspace.
   *   <li>Use mmap(2) or equivalent. Requires that either the input channel or the output channel
   *       have file descriptors. Bytes are copied from the file into a kernel buffer, then directly

        collection = mapEntry.getValue();
        valueIterator = collection.iterator();
      }
      /*
       * uncheckedCastNullableTToT is safe: The first call to this method always enters the !hasNext() case and
       * populates key, after which it's never cleared.
       */
      return output(uncheckedCastNullableTToT(key), valueIterator.next());
    }

    @Override

          currentKey = entry.getKey();
          valueItr = entry.getValue().iterator();
        }
        /*
         * requireNonNull is safe: The first call to this method always enters the !hasNext() case
         * and populates currentKey, after which it's never cleared.
         */
        return immutableEntry(requireNonNull(currentKey), valueItr.next());
      }
    };
  }

  /**