code: public static Object quoteIfString(Object obj) {
          return obj instanceof String ? quote((String) obj) : obj;
      }
docs: Turn the given Object into a String with single quotes if it is a String;
  keeping the Object as-is else.
  
  @param obj
  the input Object (e.g. "myString")
  @return the quoted String (e.g. "'myString'"), or the input object as-is
  if not a String