private static final long serialVersionUID = 1L;

    /**
     * The language/region code for this alternate link.
     * Should be in ISO 639-1 format (language) optionally followed by ISO 3166-1 Alpha 2 format (region).
     * For example: "en", "en-US", "de-CH", "x-default"
     */
    private String hreflang;

    /**
     * The URL of the alternate version of the page.
     */

  }

  /**
   * Combines four iterables into a single iterable. The returned iterable has an iterator that
   * traverses the elements in {@code a}, followed by the elements in {@code b}, followed by the
   * elements in {@code c}, followed by the elements in {@code d}. The source iterators are not
   * polled until necessary.
   *

     * The file is newline separated. The first two lines are the URL and the request method. Next
     * is the number of HTTP Vary request header lines, followed by those lines.
     *
     * Next is the response status line, followed by the number of HTTP response header lines,
     * followed by those lines.
     *
     * HTTPS responses also contain SSL session information. This begins with a blank line, and then

      // But theoretically we could see sneaky checked exception
      sneakyThrow(exception);
    }
  }

  /**
   * 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.
   *

### When Refactoring

1. Preserve behavior
2. Keep tests green
3. Small incremental steps
4. Don't mix with new features

### Code Quality Checklist

- [ ] Java conventions followed
- [ ] JavaDoc for public APIs
- [ ] Tests pass (`mvn test`)
- [ ] No compiler warnings
- [ ] Proper exception handling
- [ ] Resource cleanup (AutoCloseable)
- [ ] Thread-safe if needed

        keyIterator.remove();
      }
      totalSize--;
    }
  }

  /**
   * {@inheritDoc}
   *
   * <p>The iterator generated by the returned collection traverses the values for one key, followed
   * by the values of a second key, and so on.
   */
  @Override
  public Collection<V> values() {
    return super.values();
  }

  @Override
  Collection<V> createValues() {

   */
  open fun cacheMiss(call: Call) {
  }

  /**
   * Invoked when a response will be served from the cache or network based on validating the
   * cached Response freshness. Will be followed by cacheHit or cacheMiss after the network
   * Response is available.
   *
   * This event will only be received when a Cache is configured for the client.
   */
  open fun cacheConditionalHit(
    call: Call,

      // Expect to fail before enqueueing 32 MiB.
      assertThat(messageCount).isLessThan(32L)
    }

    // Confirm all sent messages were received, followed by a client-initiated close.
    val server = serverListener.assertOpen()
    for (i in 0 until messageCount) {
      serverListener.assertBinaryMessage(message)
    }
    serverListener.assertClosing(1001, "")

      return fromMap.containsKey(key);
    }

    @Override
    public @Nullable V2 get(@Nullable Object key) {
      return getOrDefault(key, null);
    }

    // safe as long as the user followed the <b>Warning</b> in the javadoc
    @SuppressWarnings("unchecked")
    @Override
    public @Nullable V2 getOrDefault(@Nullable Object key, @Nullable V2 defaultValue) {
      V1 value = fromMap.get(key);

     */
    fun authenticator(authenticator: Authenticator) =
      apply {
        this.authenticator = authenticator
      }

    /** Configure this client to follow redirects. If unset, redirects will be followed. */
    fun followRedirects(followRedirects: Boolean) =
      apply {
        this.followRedirects = followRedirects
      }

    /**