Preconditions.checkNotNull(executor, "Executor was null.");

      RunnableExecutorPair newHead = new RunnableExecutorPair(runnable, executor);
      RunnableExecutorPair oldHead;
      do {
        oldHead = head;
        if (oldHead == null) {
          // If runnables == null then execute() has been called so we should just execute our
          // listener immediately.
          newHead.execute();

        .testEquals();
  }

  /*
   * We use large numbers to avoid the integer cache. Normally, we'd accomplish that merely by using
   * `new Integer` (as we do) instead of `Integer.valueOf`. However, under J2KT, `new Integer`
   * gets translated back to `Integer.valueOf` because that is the only thing J2KT can support. And

   * SortedSet} values.
   */
  @Override
  public Map<K, Collection<V>> asMap() {
    return super.asMap();
  }

  /**
   * {@inheritDoc}
   *
   * <p>Consequently, the values do not follow their natural ordering or the ordering of the value
   * comparator.
   */
  @Override
  public Collection<V> values() {
    return super.values();
  }

        MapTestSuiteBuilder.using(
                new TestTypeToInstanceMapGenerator() {
                  // Other tests will verify what real, warning-free usage looks like
                  // but here we have to do some serious fudging
                  @Override
                  @SuppressWarnings({"unchecked", "rawtypes"})
                  public Map<TypeToken, Object> create(Object... elements) {

        .suppressing(suppressForLinkedBlockingQueue())
        .createTestSuite();
  }

  // Not specifying KNOWN_ORDER for PriorityQueue and PriorityBlockingQueue
  // even though they do have it, because our tests interpret KNOWN_ORDER to
  // also mean that the iterator returns the head element first, which those
  // don't.

  public Test testsForPriorityBlockingQueue() {

  // TODO: Test interrupts with both interruptible and uninterruptible monitor.
  // TODO: Test multiple waiters: If guard is still satisfied, signal next waiter.
  // TODO: Test multiple waiters: If guard is no longer satisfied, do not signal next waiter.

   * SortedSet} values.
   */
  @Override
  public Map<K, Collection<V>> asMap() {
    return super.asMap();
  }

  /**
   * {@inheritDoc}
   *
   * <p>Consequently, the values do not follow their natural ordering or the ordering of the value
   * comparator.
   */
  @Override
  public Collection<V> values() {
    return super.values();
  }

 * {@code equals} comparisons. Use caution if mutable objects are used as keys or values in a {@code
 * SetMultimap}.
 *
 * <p><b>Warning:</b> Do not modify either a key <i>or a value</i> of a {@code SetMultimap} in a way
 * that affects its {@link Object#equals} behavior. Undefined behavior and bugs will result.
 *
 * <p>See the Guava User Guide article on <a href=

      }
    } else { // non-empty list, insert before nextSibling
      /*
       * requireNonNull is safe as long as callers pass a nextSibling that (a) has the same key and
       * (b) is present in the multimap. (And they do, except maybe in case of concurrent
       * modification, in which case all bets are off.)
       */
      KeyList<K, V> keyList = requireNonNull(keyToKeyList.get(key));
      keyList.count++;

   * char} are hashed directly (in that order). The input must not be updated while this method is
   * in progress.
   *
   * <p><b>Warning:</b> This method will produce different output than most other languages do when
   * running the same hash function on the equivalent input. For cross-language compatibility, use
   * {@link #putString}, usually with a charset of UTF-8. For other use cases, use {@code
   * putUnencodedChars}.
   *