code: public static String stringifyTypeParameters(List<AbstractType<?>> types, boolean ignoreFreezing)
      {
          StringBuilder sb = new StringBuilder("(");
          for (int i = 0; i < types.size(); i++)
          {
              if (i > 0)
                  sb.append(",");
              sb.append(types.get(i).toString(ignoreFreezing));
          }
          return sb.append(')').toString();
      }
docs: Helper function to ease the writing of AbstractType.toString() methods.