socketFile.delete(); // Clean up from previous runs.

    MockWebServer server = new MockWebServer();
    server.setServerSocketFactory(new UnixDomainServerSocketFactory(socketFile));
    server.setProtocols(Collections.singletonList(Protocol.H2_PRIOR_KNOWLEDGE));
    server.enqueue(new MockResponse().setBody("hello"));
    server.start();

    OkHttpClient client = new OkHttpClient.Builder()

  fun setProtocolNegotiationEnabled(protocolNegotiationEnabled: Boolean) {
    delegate.protocolNegotiationEnabled = protocolNegotiationEnabled
  }

  @JvmName("-deprecated_protocols")
  fun setProtocols(protocols: List<Protocol>) {
    delegate.protocols = protocols
  }

  @JvmName("-deprecated_protocols")
  fun protocols(): List<Protocol> = delegate.protocols

  fun useHttps(

     */
    public String getProtocol() {
        return protocol;
    }

    /**
     * @param protocol the protocol of the proxy server like <i>SOCKSv4</i>
     */
    public void setProtocol(String protocol) {
        this.protocol = protocol;
    }

    public String getNonProxyHosts() {
        return nonProxyHosts;
    }

    public void setNonProxyHosts(String nonProxyHosts) {