// that happens, then we will have buffered bytes that are needed by the SSLSocket!
        // This check is imperfect: it doesn't tell us whether a handshake will succeed, just
        // that it will almost certainly fail because the proxy has sent unexpected data.
        if (!socket.source.buffer.exhausted() || !socket.sink.buffer.exhausted()) {
          throw IOException("TLS tunnel buffered too many bytes!")
        }

    protected ExtractData createExtractData(final String content) {
        return new ExtractData(extractString(content));
    }

    /**
     * Detects the encoding of the input stream.
     * @param bis The buffered input stream.
     * @return The detected encoding.
     */
    protected String getEncoding(final BufferedInputStream bis) {
        final byte[] b = new byte[preloadSizeForCharset];
        try {

     * Captures output from command execution with configurable line buffering.
     */
    protected static class InputStreamThread extends Thread {

        /** Buffered reader for input stream. */
        private BufferedReader br;

        /** List to store captured output lines. */
        private final List<String> list = new LinkedList<>();

    )
    val call1 = client.newCall(Request(server.url("/")))
    val response1 = call1.execute()
    waitForDataFrames(Http2Connection.OKHTTP_CLIENT_WINDOW_SIZE)

    // Cancel the call and discard what we've buffered for the response body. This should free up
    // the connection flow-control window so new requests can proceed.
    call1.cancel()
    assertThat(
      response1.body.source().discard(1, TimeUnit.SECONDS),