*/
    long deadline = System.nanoTime() + unit.toNanos(timeout);
    int added = 0;
    while (added < numElements) {
      // we could rely solely on #poll, but #drainTo might be more efficient when there are multiple
      // elements already available (e.g. LinkedBlockingQueue#drainTo locks only once)
      added += q.drainTo(buffer, numElements - added);

    return delegate().poll(timeout, unit);
  }

  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @Override
  public int drainTo(Collection<? super E> c, int maxElements) {
    return delegate().drainTo(c, maxElements);
  }

    return delegate().poll(timeout, unit);
  }

  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @Override
  public int drainTo(Collection<? super E> c, int maxElements) {
    return delegate().drainTo(c, maxElements);
  }

  protected abstract BlockingQueue<E> delegate();

  @CanIgnoreReturnValue
  @Override
  public int drainTo(Collection<? super E> c, int maxElements) {
    return delegate().drainTo(c, maxElements);
  }

  @CanIgnoreReturnValue
  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @CanIgnoreReturnValue // TODO(kak): consider removing this
  @Override

     */
    long deadline = System.nanoTime() + unit.toNanos(timeout);
    int added = 0;
    while (added < numElements) {
      // we could rely solely on #poll, but #drainTo might be more efficient when there are multiple
      // elements already available (e.g. LinkedBlockingQueue#drainTo locks only once)
      added += q.drainTo(buffer, numElements - added);

    return delegate().poll(timeout, unit);
  }

  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @Override
  public int drainTo(Collection<? super E> c, int maxElements) {
    return delegate().drainTo(c, maxElements);
  }

 * is not guaranteed to traverse the elements of the MonitorBasedPriorityBlockingQueue in
 * any particular order. If you need ordered traversal, consider using {@code
 * Arrays.sort(pq.toArray())}. Also, method {@code drainTo} can be used to remove some or
 * all elements in priority order and place them in another collection.
 *
 * <p>Operations on this class make no guarantees about the ordering of elements with equal

    ) = error("unsupported")

    override fun take() = error("unsupported")

    override fun remainingCapacity() = error("unsupported")

    override fun drainTo(sink: MutableCollection<in T>) = error("unsupported")

    override fun drainTo(
      sink: MutableCollection<in T>,
      maxElements: Int,
    ) = error("unsupported")
  }

   * @throws ClassCastException {@inheritDoc}
   * @throws NullPointerException {@inheritDoc}
   * @throws IllegalArgumentException {@inheritDoc}
   */
  @CanIgnoreReturnValue
  @Override
  public int drainTo(Collection<? super E> c) {
    checkNotNull(c);
    checkArgument(c != this);
    E[] items = this.items;
    Monitor monitor = this.monitor;
    monitor.enter();
    try {
      int i = takeIndex;

   * @throws ClassCastException {@inheritDoc}
   * @throws NullPointerException {@inheritDoc}
   * @throws IllegalArgumentException {@inheritDoc}
   */
  @CanIgnoreReturnValue
  @Override
  public int drainTo(Collection<? super E> c) {
    checkNotNull(c);
    checkArgument(c != this);
    E[] items = this.items;
    Monitor monitor = this.monitor;
    monitor.enter();
    try {
      int i = takeIndex;