Concurrency
===========

This document describes the concurrency considerations for http/2 connections and the connection pool within OkHttp.

## HTTP/2 Connections

The HttpURLConnection API is a blocking API. You make a blocking write to send a request, and a blocking read to receive the response.

#### Blocking APIs

This will skip the normal events such as DNS, connecting to the network, and downloading the response body.

As recommended by the HTTP RFC the max age of a document is defaulted to 10% of the 
document's age at the time it was served based on "Last-Modified". Default expiration dates aren't used for URIs 
containing a query.

 - CallStart
 - **CacheHit**
 - CallEnd
 
### Cache Miss

      if (mediaType == null || !mediaType.subtype().equalsIgnoreCase("html")) {
        return;
      }

      Document document = Jsoup.parse(response.body().string(), url.toString());
      for (Element element : document.select("a[href]")) {
        String href = element.attr("href");
        HttpUrl link = response.request().url().resolve(href);

## Follow-up Requests

When your requested URL has moved, the webserver will return a response code like `302` to indicate the document’s new URL. OkHttp will follow the redirect to retrieve a final response.

   */
  var typeHint: Any?
    get() = typeHintStack.lastOrNull()
    set(value) {
      typeHintStack[typeHintStack.size - 1] = value
    }

  /** Names leading to the current location in the ASN.1 document. */
  private val path = mutableListOf<String>()

  /**
   * False unless we made a recursive call to [write] at the current stack frame. The explicit box