@Override
    public void turnOn(int index) {
        this.userSettings.set(index);
    }
Init with system default value
  if settings exist by system property then use system property at first;
  if no settings exist by system property then use default value in {@link com.alipay.remoting.config.Configs}
All these settings can be overwrite by user api settings.
src/main/java/com/alipay/remoting/config/switches/GlobalSwitch.java