*   <li><a href="http://www.ietf.org/rfc/rfc5988.txt">RFC 5988</a>
 * </ul>
 *
 * @author Kurt Alfred Kluever
 * @since 11.0
 */
@GwtCompatible
public final class HttpHeaders {
  private HttpHeaders() {}

  // HTTP Request and Response header fields

  /** The HTTP {@code Cache-Control} header field name. */
  public static final String CACHE_CONTROL = "Cache-Control";

          httpHeaders.add(name, value)
        } else {
          throw IllegalStateException()
        }
        if (name == "expect" && value.equals("100-continue", ignoreCase = true)) {
          // Don't read the body unless we've invited the client to send it.
          readBody = false
        }
      }
      val headers = httpHeaders.build()

      val peek = dispatcher.peek()

_2019-07-10_

 *  Fix: Tolerate null-hostile lists in public API. Lists created with `List.of(...)` don't like it
    when you call `contains(null)` on them!
 *  Fix: Retain binary-compatibility in `okhttp3.internal.HttpHeaders.hasBody()`. Some unscrupulous
    coders call this and we don't want their users to suffer.


## Version 4.0.0

_2019-06-26_