@CheckForNull
  K getKey();

  /*
   * Used by entries that use access order. Access entries are maintained in a doubly-linked list.
   * New entries are added at the tail of the list at write time; stale entries are expired from
   * the head of the list.
   */

  /** Returns the time that this entry was last accessed, in ns. */
  @SuppressWarnings("GoodTime")
  long getAccessTime();

        else if (a.cas(v = a.value, fn(v, x))) break;
        else if (n >= NCPU || cells != as) collide = false; // At max size or stale
        else if (!collide) collide = true;
        else if (busy == 0 && casBusy()) {
          try {
            if (cells == as) { // Expand table unless stale
              Cell[] rs = new Cell[n << 1];
              for (int i = 0; i < n; ++i) rs[i] = as[i];
              cells = rs;

  @CheckForNull
  K getKey();

  /*
   * Used by entries that use access order. Access entries are maintained in a doubly-linked list.
   * New entries are added at the tail of the list at write time; stale entries are expired from
   * the head of the list.
   */

  /** Returns the time that this entry was last accessed, in ns. */
  @SuppressWarnings("GoodTime")
  long getAccessTime();

        else if (a.cas(v = a.value, fn(v, x))) break;
        else if (n >= NCPU || cells != as) collide = false; // At max size or stale
        else if (!collide) collide = true;
        else if (busy == 0 && casBusy()) {
          try {
            if (cells == as) { // Expand table unless stale
              Cell[] rs = new Cell[n << 1];
              for (int i = 0; i < n; ++i) rs[i] = as[i];
              cells = rs;

        else if (a.cas(v = a.value, fn(v, x))) break;
        else if (n >= NCPU || cells != as) collide = false; // At max size or stale
        else if (!collide) collide = true;
        else if (busy == 0 && casBusy()) {
          try {
            if (cells == as) { // Expand table unless stale
              Cell[] rs = new Cell[n << 1];
              for (int i = 0; i < n; ++i) rs[i] = as[i];
              cells = rs;

    service.startAsync().awaitRunning();
    assertEquals(State.RUNNING, service.state());

    service.stopAsync();
    service.stopAsync();
    assertEquals(State.TERMINATED, service.state());
    assertEquals(
        ImmutableList.of(State.STARTING, State.RUNNING, State.STOPPING, State.TERMINATED),
        listener.getStateHistory());
  }

   * implementation; otherwise refreshes will be performed during unrelated cache read and write
   * operations.
   *
   * <p>Currently automatic refreshes are performed when the first stale request for an entry
   * occurs. The request triggering refresh will make a synchronous call to {@link
   * CacheLoader#reload}
   * to obtain a future of the new value. If the returned future is already complete, it is returned

  double storedPermits;

  /** The maximum number of stored permits. */
  double maxPermits;

  /**
   * The interval between two unit requests, at our stable rate. E.g., a stable rate of 5 permits
   * per second has a stable interval of 200ms.
   */
  double stableIntervalMicros;

  /**
   * The time when the next request (no matter its size) will be granted. After granting a request,

    service.startAsync().awaitRunning();
    assertEquals(State.RUNNING, service.state());

    service.stopAsync();
    service.stopAsync();
    assertEquals(State.TERMINATED, service.state());
    assertEquals(
        ImmutableList.of(State.STARTING, State.RUNNING, State.STOPPING, State.TERMINATED),
        listener.getStateHistory());
  }

   * implementation; otherwise refreshes will be performed during unrelated cache read and write
   * operations.
   *
   * <p>Currently automatic refreshes are performed when the first stale request for an entry
   * occurs. The request triggering refresh will make a synchronous call to {@link
   * CacheLoader#reload}
   * and immediately return the new value if the returned future is complete, and the old value