code: public static Map<String, List<Object>> getListMap(Message message, List<ExpressionMapping> expressionMappings, boolean expand, String undefinedVariable) {
          return getListMap(message, expressionMappings, expand, undefinedVariable, null);
      }
docs: Gets a list map.
  
  @param message the message
  @param expressionMappings the expression mappings
  @param expand whether to expand
  @param undefinedVariable the undefined variable name
  @return the list map