code: protected void startServerImpl() {
          SelendroidLogger.info("*** ServerInstrumentation#startServerImpl() ***");
          if (serverThread != null && serverThread.isAlive()) {
              return;
          }
  
          if (serverThread != null) {
              stopServer();
          }
  
          serverThread = new HttpdThread(this, serverPort);
          serverThread.startServer();
      }
docs: specific logic to a subclass