* @throws IllegalStateException if a ticker was already set
   */
  @CanIgnoreReturnValue
  public CacheBuilder<K, V> ticker(Ticker ticker) {
    checkState(this.ticker == null);
    this.ticker = checkNotNull(ticker);
    return this;
  }

  Ticker getTicker(boolean recordsTime) {
    if (ticker != null) {
      return ticker;
    }
    return recordsTime ? Ticker.systemTicker() : NULL_TICKER;
  }

            return Futures.immediateFuture(two);
          }
        };

    LoadingCache<Object, Object> cache =
        CacheBuilder.newBuilder()
            .recordStats()
            .ticker(ticker)
            .refreshAfterWrite(1, MILLISECONDS)
            .build(loader);
    Object key = new Object();
    CacheStats stats = cache.stats();
    assertEquals(0, stats.missCount());

   * @throws IllegalStateException if a ticker was already set
   */
  @CanIgnoreReturnValue
  public CacheBuilder<K, V> ticker(Ticker ticker) {
    checkState(this.ticker == null);
    this.ticker = checkNotNull(ticker);
    return this;
  }

  Ticker getTicker(boolean recordsTime) {
    if (ticker != null) {
      return ticker;
    }
    return recordsTime ? Ticker.systemTicker() : NULL_TICKER;
  }

		},
		{
			val:   0.79,
			label: labels[2],
		},
	}
	ticker := time.NewTicker(1 * time.Millisecond)
	defer ticker.Stop()
	for _, obs := range observations {
		// Send observations once every 1ms, to simulate delay between
		// observations. This is to test the channel based
		// synchronization used internally.
		select {
		case <-ticker.C:
			ttfbHist.With(prometheus.Labels{"api": obs.label}).Observe(obs.val)
		}

    checkNotNull(ticker);
    expireEntries(toLocalCache(cache), expiringTime, ticker);
  }

  static void expireEntries(LocalCache<?, ?> cchm, long expiringTime, FakeTicker ticker) {

    for (Segment<?, ?> segment : cchm.segments) {
      drainRecencyQueue(segment);
    }

    ticker.advance(2 * expiringTime, TimeUnit.MILLISECONDS);

			} else {
				write([]byte{0})
			}
			xioutil.SafeClose(doneCh)
			return
		}
		defer xioutil.SafeClose(doneCh)
		// Initiate ticker after body has been read.
		ticker := time.NewTicker(time.Second * 10)
		defer ticker.Stop()

		for {
			select {
			case <-ticker.C:
				// The done() might have been called
				// concurrently, check for it before we
				// write the filler byte.
				select {

      this.maxWeight = maxWeight;
      this.weigher = weigher;
      this.concurrencyLevel = concurrencyLevel;
      this.removalListener = removalListener;
      this.ticker = (ticker == Ticker.systemTicker() || ticker == NULL_TICKER) ? null : ticker;
      this.loader = loader;
    }

    CacheBuilder<K, V> recreateCacheBuilder() {
      CacheBuilder<K, V> builder =
          CacheBuilder.newBuilder()

      this.maxWeight = maxWeight;
      this.weigher = weigher;
      this.concurrencyLevel = concurrencyLevel;
      this.removalListener = removalListener;
      this.ticker = (ticker == Ticker.systemTicker() || ticker == NULL_TICKER) ? null : ticker;
      this.loader = loader;
    }

    CacheBuilder<K, V> recreateCacheBuilder() {
      CacheBuilder<K, V> builder =
          CacheBuilder.newBuilder()

  }

  public void testTicker_setTwice() {
    Ticker testTicker = Ticker.systemTicker();
    CacheBuilder<Object, Object> builder = CacheBuilder.newBuilder().ticker(testTicker);
    try {
      // even to the same instance is not allowed
      builder.ticker(testTicker);
      fail();
    } catch (IllegalStateException expected) {
    }
  }

     * Program will use this name to require service ticket from KDC.
     *
     * @param name
     *            the service name used to require service ticket from KDC.
     */
    public void setService ( String name ) {
        this.service = name;
    }


    /**
     * Get the service name.
     *
     * @return the service name used to require service ticket from KDC
     */