next = (keyList == null) ? null : keyList.head;
    }

    /**
     * Constructs a new iterator over all values for the specified key starting at the specified
     * index. This constructor is optimized so that it starts at either the head or the tail,
     * depending on which is closer to the specified index. This allows adds to the tail to be done
     * in constant time.
     *
     * @throws IndexOutOfBoundsException if index is invalid

        }
      };

  /**
   * A Throwable used to record a stack trace that illustrates an example of a specific lock
   * acquisition ordering. The top of the stack trace is truncated such that it starts with the
   * acquisition of the lock in question, e.g.
   *
   * <pre>
   * com...ExampleStackTrace: LockB -&gt; LockC
   *   at com...CycleDetectingReentrantLock.lock(CycleDetectingLockFactory.java:443)

    }
    final ReentrantLock lock = this.lock;
    boolean reentrant = lock.isHeldByCurrentThread();
    long startTime = 0L;

    locked:
    {
      if (!fair) {
        // Check interrupt status to get behavior consistent with fair case.
        if (Thread.interrupted()) {
          throw new InterruptedException();
        }
        if (lock.tryLock()) {
          break locked;
        }
      }

        totalCount = laterCount = currentEntry.getCount();
      }
      laterCount--;
      canRemove = true;
      /*
       * requireNonNull is safe because laterCount starts at 0, forcing us to initialize
       * currentEntry above. After that, we never clear it.
       */
      return requireNonNull(currentEntry).getElement();
    }

    @Override

 *
 * <pre>{@code
 * Bill bill = remoteService.getLastUnpaidBill();
 *
 * // In case bug 12345 happens again we'd rather just die
 * Verify.verify(bill.status() == Status.UNPAID,
 *     "Unexpected bill status: %s", bill.status());
 * }</pre>
 *
 * <h3>Comparison to alternatives</h3>
 *
 * <p><b>Note:</b> In some cases the differences explained below can be subtle. When it's unclear

    WaiterThread waiter = new WaiterThread(future);
    waiter.start();
    waiter.awaitWaiting();
    PollingThread poller = new PollingThread(future);
    poller.start();
    PollingThread poller2 = new PollingThread(future);
    poller2.start();
    PollingThread poller3 = new PollingThread(future);
    poller3.start();
    poller.awaitInLoop();
    poller2.awaitInLoop();
    poller3.awaitInLoop();

    return NANOSECONDS.toMillis(System.nanoTime() - startNanoTime);
  }

  /** Returns a new started daemon Thread running the given runnable. */
  Thread newStartedThread(Runnable runnable) {
    Thread t = new Thread(runnable);
    t.setDaemon(true);
    t.start();
    return t;
  }

  /**
   * Waits for the specified time (in milliseconds) for the thread to terminate (using {@link

    }
  }

  private static void assertIntactUsingStartedWith(
      Collection<?> startedWith, MinMaxPriorityQueue<?> q) {
    if (!q.isIntact()) {
      fail("Started with " + startedWith + ". State " + Arrays.toString(q.toArray()));
    }
  }

  private static void assertEqualsUsingSeed(
      long seed, @Nullable Object expected, @Nullable Object actual) {

        || validSurrogatePairAt(b, b.length() - s - 1)) {
      s--;
    }
    return a.subSequence(a.length() - s, a.length()).toString();
  }

  /**
   * True when a valid surrogate pair starts at the given {@code index} in the given {@code string}.
   * Out-of-range indexes return false.
   */
  @VisibleForTesting
  static boolean validSurrogatePairAt(CharSequence string, int index) {
    return index >= 0

     * its own "running" check.
     */
    void awaitRunChecks() throws InterruptedException {
      assertTrue(
          "Service thread hasn't finished its checks. "
              + "Exception status (possibly stale): "
              + thrownByExecutionThread,
          hasConfirmedIsRunning.await(10, SECONDS));
    }

    @Override
    protected void doStart() {
      assertEquals(State.STARTING, state());