private static final sun.misc.Unsafe UNSAFE;
    private static final long HEAD_OFFSET;

    /**
     * A special instance of {@link RunnableExecutorPair} that is used as a sentinel value for the
     * bottom of the stack.
     */
    private static final RunnableExecutorPair NULL_PAIR = new RunnableExecutorPair(null, null);

    static {
      try {
        UNSAFE = getUnsafe();

  // is masked in order to correspond to the current table size. For example, if the table size
  // is 128 then the mask is 127 == 0x7f, keeping the bottom 7 bits of the hash value.
  // If a key hashes to 0x89abcdef the mask reduces it to 0x89abcdef & 0x7f == 0x6f. We'll call this
  // the "short hash".
  //

  // non-null instance of Ordering.natural().
  // (cpovirk: Is sortedDelegate's comparator really ever null?)
  // The comparator will likely also differ because of our nullAccepting hack.
  // See the bottom of the file for more information about it.
  private final transient Comparator<? super K> comparator;

  ImmutableSortedMap(SortedMap<K, V> delegate, Comparator<? super K> comparator) {
    super(delegate);

it every now and then, and holding it to his ear.

  Alice considered a little, and then said `The fourth.'

  `Two days wrong!' sighed the Hatter.  `I told you butter
wouldn't suit the works!' he added looking angrily at the March
Hare.

  `It was the BEST butter,' the March Hare meekly replied.

  `Yes, but some crumbs must have got in as well,' the Hatter
grumbled:  `you shouldn't have put it in with the bread-knife.'

    private static final sun.misc.Unsafe UNSAFE;
    private static final long HEAD_OFFSET;

    /**
     * A special instance of {@link RunnableExecutorPair} that is used as a sentinel value for the
     * bottom of the stack.
     */
    private static final RunnableExecutorPair NULL_PAIR = new RunnableExecutorPair(null, null);

    static {
      try {
        UNSAFE = getUnsafe();

 * graph.putEdge("chocolate", "peanut butter");
 * graph.putEdge("peanut butter", "jelly");
 *
 * // Building an immutable graph
 * ImmutableGraph<String> immutableGraph =
 *     GraphBuilder.undirected()
 *         .allowsSelfLoops(true)
 *         .<String>immutable()
 *         .putEdge("bread", "bread")
 *         .putEdge("chocolate", "peanut butter")
 *         .putEdge("peanut butter", "jelly")
 *         .build();
 * }</pre>

    // The top bit is set, which means that the double value is going to come from the top 53 bits.
    // So we can ignore the bottom 11, except for rounding. We can unsigned-shift right 1, aka
    // unsigned-divide by 2, and convert that. Then we'll get exactly half of the desired double
    // value. But in the specific case where the bottom two bits of the original number are 01, we
    // want to replace that with 1 in the shifted value for correct rounding.

  public V get(long timeout, TimeUnit unit)
      throws InterruptedException, TimeoutException, ExecutionException {
    // NOTE: if timeout < 0, remainingNanos will be < 0 and we will fall into the while(true) loop
    // at the bottom and throw a timeoutexception.
    final long timeoutNanos = unit.toNanos(timeout); // we rely on the implicit null check on unit.
    long remainingNanos = timeoutNanos;
    if (Thread.interrupted()) {

    Heap heap = heapForIndex(index);
    // We consider elementData(index) a "hole", and we want to fill it
    // with the last element of the heap, toTrickle.
    // Since the last element of the heap is from the bottom level, we
    // optimistically fill index position with elements from lower levels,
    // moving the hole down. In most cases this reduces the number of

it every now and then, and holding it to his ear.

  Alice considered a little, and then said `The fourth.'

  `Two days wrong!' sighed the Hatter.  `I told you butter
wouldn't suit the works!' he added looking angrily at the March
Hare.

  `It was the BEST butter,' the March Hare meekly replied.

  `Yes, but some crumbs must have got in as well,' the Hatter
grumbled:  `you shouldn't have put it in with the bread-knife.'