* we change the rate.
   */
  public void testWeNeverGetABurstMoreThanOneSec() {
    RateLimiter limiter = RateLimiter.create(1.0, stopwatch);
    int[] rates = {1000, 1, 10, 1000000, 10, 1};
    for (int rate : rates) {
      int oneSecWorthOfWork = rate;
      stopwatch.sleepMillis(rate * 1000);
      limiter.setRate(rate);

   * we change the rate.
   */
  public void testWeNeverGetABurstMoreThanOneSec() {
    RateLimiter limiter = RateLimiter.create(1.0, stopwatch);
    int[] rates = {1000, 1, 10, 1000000, 10, 1};
    for (int rate : rates) {
      int oneSecWorthOfWork = rate;
      stopwatch.sleepMillis(rate * 1000);
      limiter.setRate(rate);

 * late. Also, all life cycle methods are executed with a lock held, so subclasses can safely modify
 * shared state without additional synchronization necessary for visibility to later executions of
 * the life cycle methods.
 *
 * <h3>Usage Example</h3>
 *
 * <p>Here is a sketch of a service which crawls a website and uses the scheduling capabilities to
 * rate limit itself.
 *
 * <pre>{@code

   *
   * The Least Recently Used page replacement algorithm was chosen due to its simplicity, high hit
   * rate, and ability to be implemented with O(1) time complexity. The initial LRU implementation
   * operates per-segment rather than globally for increased implementation simplicity. We expect
   * the cache hit rate to be similar to that of a global LRU algorithm.
   */

  // Constants

  /**

   *
   * The Least Recently Used page replacement algorithm was chosen due to its simplicity, high hit
   * rate, and ability to be implemented with O(1) time complexity. The initial LRU implementation
   * operates per-segment rather than globally for increased implementation simplicity. We expect
   * the cache hit rate to be similar to that of a global LRU algorithm.
   */

  // Constants

  /**

   *
   * <p>See http://en.wikipedia.org/wiki/Bloom_filter#Probability_of_false_positives for the
   * formula.
   *
   * @param n expected insertions (must be positive)
   * @param p false positive rate (must be 0 < p < 1)
   */
  @VisibleForTesting
  static long optimalNumOfBits(long n, double p) {
    if (p == 0) {
      p = Double.MIN_VALUE;
    }

   * out.
   */
  long timeoutMillis() {
    return SHORT_DELAY_MS / 4;
  }

  /** Returns a new Date instance representing a time delayMillis milliseconds in the future. */
  Date delayedDate(long delayMillis) {
    return new Date(System.currentTimeMillis() + delayMillis);
  }

  /** The first exception encountered if any threadAssertXXX method fails. */

   * to hang (possibly too quickly, but too-quick failures should be very unlikely, given that we
   * used to bail after 20ms during the expected-successful tests, and there we saw a failure rate
   * of ~1/5000, meaning that the other thread's get() call nearly always completes within 20ms if
   * it's going to complete at all).
   *

  final Policy policy;

  private CycleDetectingLockFactory(Policy policy) {
    this.policy = checkNotNull(policy);
  }

  /**
   * Tracks the currently acquired locks for each Thread, kept up to date by calls to {@link
   * #aboutToAcquire(CycleDetectingLock)} and {@link #lockStateChanged(CycleDetectingLock)}.
   */
  // This is logically a Set, but an ArrayList is used to minimize the amount

   * to hang (possibly too quickly, but too-quick failures should be very unlikely, given that we
   * used to bail after 20ms during the expected-successful tests, and there we saw a failure rate
   * of ~1/5000, meaning that the other thread's get() call nearly always completes within 20ms if
   * it's going to complete at all).
   *