}
  }

  /**
   * Returns a {@link Stream} containing the elements of the first stream, followed by the elements
   * of the second stream, and so on.
   *
   * <p>This is equivalent to {@code Stream.of(streams).flatMap(stream -> stream)}, but the returned
   * stream may perform better.
   *
   * @see Stream#concat(Stream, Stream)
   */

   * iterator supports it.
   *
   * <p><b>{@code Stream} equivalent:</b> to concatenate an arbitrary number of streams, use {@code
   * Stream.of(stream1, stream2, ...).flatMap(s -> s)}. If the sources are iterables, use {@code
   * Stream.of(iter1, iter2, ...).flatMap(Streams::stream)}.
   *
   * @throws NullPointerException if any of the provided iterables is {@code null}
   * @since 20.0

  }

  /**
   * Concatenates multiple {@link ByteSource} instances into a single source. Streams returned from
   * the source will contain the concatenated data from the streams of the underlying sources.
   *
   * <p>Only one underlying stream will be open at a time. Closing the concatenated stream will
   * close the open underlying stream.
   *
   * @param sources the sources to concatenate

  }

  /**
   * Concatenates multiple {@link CharSource} instances into a single source. Streams returned from
   * the source will contain the concatenated data from the streams of the underlying sources.
   *
   * <p>Only one underlying stream will be open at a time. Closing the concatenated stream will
   * close the open underlying stream.
   *
   * @param sources the sources to concatenate

  }

  /**
   * Concatenates multiple {@link CharSource} instances into a single source. Streams returned from
   * the source will contain the concatenated data from the streams of the underlying sources.
   *
   * <p>Only one underlying stream will be open at a time. Closing the concatenated stream will
   * close the open underlying stream.
   *
   * @param sources the sources to concatenate

   * chosen. Guarded by this.
   */
  internal var routeFailureCount = 0

  private var successCount = 0
  private var refusedStreamCount = 0

  /**
   * The maximum number of concurrent streams that can be carried by this connection. If
   * `allocations.size() < allocationLimit` then new streams can be created on this connection.
   */

   * RandomAccess} support, then this operation is guaranteed to be {@code O(1)}.
   *
   * <p><b>{@code Stream} equivalent:</b> {@link Streams#findLast Streams.findLast(stream).get()}
   *
   * <p><b>Java 21+ users:</b> if {code iterable} is a {@code SequencedCollection} (e.g., any list),
   * consider using {@code collection.getLast()} instead.
   *

 * well.
 *
 * <h3>Java 8+ users</h3>
 *
 * <p>If you are using Java 8+, this class is now obsolete. Most of its functionality is now
 * provided by {@link java.util.stream.Stream Stream} and by {@link Comparator} itself, and the rest
 * can now be found as static methods in our new {@link Comparators} class. See each method below

 * layer primitives: connections, requests, responses, and streams.
 *
 * This class supports [asynchronous canceling][cancel]. This is intended to have the smallest
 * blast radius possible. If an HTTP/2 stream is active, canceling will cancel that stream but not
 * the other streams sharing its connection. But if the TLS handshake is still in progress then
 * canceling may break the entire connection.

   * RandomAccess} support, then this operation is guaranteed to be {@code O(1)}.
   *
   * <p><b>{@code Stream} equivalent:</b> {@link Streams#findLast Streams.findLast(stream).get()}
   *
   * <p><b>Java 21+ users:</b> if {code iterable} is a {@code SequencedCollection} (e.g., any list),
   * consider using {@code collection.getLast()} instead.
   *