protected static Object getParamArg(Class cl)
  {
    if (! cl.isPrimitive())
      return null;
    else if (boolean.class.equals(cl))
      return Boolean.FALSE;
    else if (byte.class.equals(cl))
      return new Byte((byte) 0);
    else if (short.class.equals(cl))
      return new Short((short) 0);
    else if (char.class.equals(cl))
      return new Character((char) 0);
    else if (int.class.equals(cl))
      return Integer.valueOf(0);
    else if (long.class.equals(cl))
      return Long.valueOf(0);
    else if (float.class.equals(cl))
      return Float.valueOf(0);
    else if (double.class.equals(cl))
      return Double.valueOf(0);
    else
      throw new UnsupportedOperationException();
  }