System.out.println("REQUEST 1 (new connection)");
try (Response response = client.newCall(request).execute()) {
  // Consume and discard the response body.
  response.body().source().readByteString();
}

System.out.println("REQUEST 2 (pooled connection)");
try (Response response = client.newCall(request).execute()) {
  // Consume and discard the response body.
  response.body().source().readByteString();
}
```

 * follow-up requests. The client is unblocked and free to continue as soon as it has received the
 * entire response body. If and when the client makes a subsequent request using a pooled socket the
 * server may not have had time to close the socket. The socket will be closed at an indeterminate
 * point before or during the second request. It may be closed after client has started sending the

 * **Exchange** carries a single HTTP request/response pair.

 * **ExchangeFinder** chooses which connection carries each exchange. Where possible it will use the same connection for all exchanges in a single call. It prefers reusing pooled connections over establishing new connections.      

#### Per-Connection Locks

 * Fix: Support the `PATCH` method.
 * Fix: Support request bodies on `DELETE` method.
 * Fix: Drop the `okhttp-protocols` module.
 * Internal: Replaced internal byte array buffers with pooled buffers ("OkBuffer").


## Version 1.3.0

_2014-01-11_

 * New: Support for "PATCH" HTTP method in client and MockWebServer.
 * Fix: Drop `Content-Length` header when redirected from POST to GET.

## Retrying Requests

Sometimes connections fail: either a pooled connection was stale and disconnected, or the webserver itself couldn’t be reached. OkHttp will retry the request with a different route if one is available.

## [Calls](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-call/)

If there's a problem with the connection, OkHttp will select another route and try again. This allows OkHttp to recover when a subset of a server's addresses are unreachable. It's also useful when a pooled connection is stale or if the attempted TLS version is unsupported.

 *     available routes.
 *
 * If the pool gains an eligible connection while DNS, TCP, or TLS work is in flight, this finder
 * will prefer pooled connections. Only pooled HTTP/2 connections are used for such de-duplication.
 *
 * It is possible to cancel the finding process by canceling its call.
 *

    try (Response response = client.newCall(request).execute()) {
      // Consume and discard the response body.
      response.body().source().readByteString();
    }

    System.out.println("REQUEST 2 (pooled connection)");
    try (Response response = client.newCall(request).execute()) {
      // Consume and discard the response body.
      response.body().source().readByteString();
    }
  }