code: static private Object effectiveParamValue(
        Map<String, Object> parameters,
        String paramName)
    {
      String upper = paramName.toUpperCase();
      Object value = parameters.get(upper);
  
      if (value != null)
      {
        return value;
      }
  
      value = defaultParameters.get(upper);
      if (value != null)
      {
        return value;
      }
  
      logger.debug("Unknown Common Parameter: {}", paramName);
      return null;
    }
docs: Returns the effective parameter value, using the value explicitly
  provided in parameters, or the default if absent
  
  @param parameters keyed in parameter name and valued in parameter value
  @param paramName  Parameter to return the value of
  @return Effective value