code: private void addUserProvidersToMap(Map<String, String> propertiesMap) {
          if (userDefinedProviders.length != 0) {
              for (PropertiesProvider provider : userDefinedProviders) {
                  propertiesMap.putAll(provider.getProperties());
              }
          }
      }
docs: Add user defined {@code PropertiesProvider} to global properties.
  
  @param propertiesMap the global properties map.