code: public static synchronized void install(AbstractConfiguration config) throws IllegalStateException {
          if (!customConfigurationInstalled) {
              setDirect(config);
              if (DynamicPropertyFactory.getBackingConfigurationSource() != config) {                
                  DynamicPropertyFactory.initWithConfigurationSource(config);
              }
          } else {
              throw new IllegalStateException("A non-default configuration is already installed");
          }
      }
docs: Install the system wide configuration with the ConfigurationManager. This will also install
  the configuration with the {@link DynamicPropertyFactory} by calling {@link DynamicPropertyFactory#initWithConfigurationSource(AbstractConfiguration)}.
  This call can be made only once, otherwise IllegalStateException will be thrown.