code: protected List<String> parseStringList( TokenStream tokens ) {
          List<String> strings = new ArrayList<String>();
          if (tokens.canConsume('?')) {
              // This list is variant ...
              strings.add("?");
          } else {
              // Read names until we see a ','
              do {
                  strings.add(removeQuotes(tokens.consume()));
              } while (tokens.canConsume(','));
          }
          return strings;
      }
docs: Parse a list of strings, separated by commas. Any quotes surrounding the strings are removed.
  
  @param tokens the tokens containing the comma-separated strings; never null
  @return the list of string values; never null, but possibly empty
  @throws ParsingException if there is a problem parsing the content