如何将用户定义的对象转换为字节数组

Question

我正在尝试将我定义的名为 lineId 的对象转换为字节数组，以便将其反馈给OutputStream.write

static void serialize(IACLineSegment objectToSerialze, OutputStream outputStream) {
    ConductingEquipmentSerializer.serialize(objectToSerialze, outputStream);
    byte[] bytes
    ID lineId = objectToSerialze.getLine().getId();
    if (lineId != null){
      outputStream.write(//lineId byte array);
      }