在子类化服务器时，
　 public class RMIServer extends UnicastRemoteObject implements RMIIterface
{ private Vector data=new Vector();

---

private void addRecord(String s1,String s2)
{ Vector details=new Vector();
details.addElement(s1); details.addElement(s2);
data.addElement(details);
details.addElement(s2); details.addElement(s1);
data.addElement(details);
}
}
为什么两个参数要交换一后再输入一次？