private OpCodes(Class<?> c)
  {
    System.out.println("Start " + c);
    for (Field f : c.getFields())
      try {
        OpCode opCode = new OpCode(f.getName(), f.getInt(null));
        this.codes.put(opCode.name.toUpperCase(), opCode);
        ids.put(opCode.value, opCode);
      } catch (Exception e) {
        e.printStackTrace();
      }
  }