class Log4JConfigurationMXBeanSingleton implements Log4JConfigurationMXBean {

    @Override
    public final void setConfigurationFile(String configFile) {
        if (configFile == null) {
            throw new IllegalArgumentException("config file may not be null");
        }
        synchronized (MONITOR) {
            if(this.updateFrequency != null) {
                throw new IllegalStateException("Can't set config file after polling has started");
            }
            this.configFile = configFile;
        }
        configure(configFile);
    }

      Log4JConfigurationMXBeanSingleton();

}