        if (o instanceof String[]) {
          return (String[]) o;
        }
        if (o instanceof String) {
          String s =  (String) o;
          return s.split(",[ ]*");
        }
        else if (o instanceof List) {
          List c = (List) o;
          String[] result = new String[c.size()]; 
          for (int i=0; i <= c.size(); i++) {
            result[i] = String.valueOf(c.get(i));
          }
          return result;
        }
        return new String[0];
    
