Serializable Error With ResultSet!!

Question

Any help???? Pls.
Here is the error!!
RemoteException
java.rmi.UnmarshalException: error unmarshalling return; nested exception is:
        java.io.WriteAbortedException: writing aborted; java.io.NotSerializableE
xception: com.microsoft.jdbc.base.BaseResultSet
java.rmi.UnmarshalException: error unmarshalling return; nested exception is:
        java.io.WriteAbortedException: writing aborted; java.io.NotSerializableE
xception: com.microsoft.jdbc.base.BaseResultSet
        at sun.rmi.server.UnicastRef.invoke(Unknown Source)
        at DBAdmin_Stub.getTimetable(Unknown Source)
        at DBClient.getTimetable(DBClient.java:18)
        at ClientDatabase.actionPerformed(ClientDatabase.java:331)
        at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
        at javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(Unknow
n Source)
        at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
        at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Sour
ce)
        at java.awt.Component.processMouseEvent(Unknown Source)
        at java.awt.Component.processEvent(Unknown Source)
        at java.awt.Container.processEvent(Unknown Source)
        at java.awt.Component.dispatchEventImpl(Unknown Source)
        at java.awt.Container.dispatchEventImpl(Unknown Source)
        at java.awt.Component.dispatchEvent(Unknown Source)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
        at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
        at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
        at java.awt.Container.dispatchEventImpl(Unknown Source)
        at java.awt.Window.dispatchEventImpl(Unknown Source)
        at java.awt.Component.dispatchEvent(Unknown Source)
        at java.awt.EventQueue.dispatchEvent(Unknown Source)
        at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
        at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
        at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
        at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.io.WriteAbortedException: writing aborted; java.io.NotSerializab
leException: com.microsoft.jdbc.base.BaseResultSet
        at java.io.ObjectInputStream.readObject0(Unknown Source)
        at java.io.ObjectInputStream.readObject(Unknown Source)
        at sun.rmi.server.UnicastRef.unmarshalValue(Unknown Source)
        ... 27 more
Caused by: java.io.NotSerializableException: com.microsoft.jdbc.base.BaseResultS
et
        at java.io.ObjectOutputStream.writeObject0(Unknown Source)
        at java.io.ObjectOutputStream.writeObject(Unknown Source)
        at sun.rmi.server.UnicastRef.marshalValue(Unknown Source)
        at sun.rmi.server.UnicastServerRef.dispatch(Unknown Source)
        at sun.rmi.transport.Transport$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.rmi.transport.Transport.serviceCall(Unknown Source)
        at sun.rmi.transport.tcp.TCPTransport.handleMessages(Unknown Source)
        at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(Unknown Sour
ce)
        at java.lang.Thread.run(Unknown Source)
Error: java.lang.NullPointerExceptionhere is the code.
import java.rmi.*;
import java.rmi.server.*;
import java.io.*;
import Database.*;
import java.sql.ResultSet;
public class DBAdmin extends UnicastRemoteObject implements DBAdminInterface, Serializable{
    private String result;
    private ResultSet tt;
    public DBAdmin() throws RemoteException {
        super();
    public String updateTimetable(int id, String year, String group, String day, String time, String room, String lecturer, String subject)throws RemoteException {
        DBUpdate update = new DBUpdate();
        result = (String) update.updateTimetable(id, year, group, day, time, room, lecturer, subject);
        return result;
    public ResultSet getTimetable(String year, String group, String day) throws RemoteException{
          DBUpdate update = new DBUpdate();
          try{
               tt = (ResultSet) update.getTimetable( year, group, day);
               if(tt == null){
                    System.out.println("Null 1");
          catch(Exception e){
               e.printStackTrace();
        return tt;
import java.rmi.*;
import java.io.*;
import java.sql.ResultSet;
public interface DBAdminInterface extends Remote, Serializable {
  public String updateTimetable(int id, String year, String group, String day, String time, String room, String lecturer, String subject) throws RemoteException;
  public ResultSet getTimetable(String year, String group, String day) throws RemoteException;
import java.net.MalformedURLException;
import java.rmi.*;
import java.sql.ResultSet;
import java.io.*;
public class DBClient implements Serializable{
    private String result;
    private ResultSet tt;
    public ResultSet getTimetable(String year, String group, String day){
      if (System.getSecurityManager() == null) {
       System.setSecurityManager(new RMISecurityManager());
      try {
           DBAdminInterface db = (DBAdminInterface) Naming.lookup ("rmi://localhost/DBAdmin");
           tt = (ResultSet) db.getTimetable(year, group, day);
           if(tt == null){
                              System.out.println("Null 1");
      catch (MalformedURLException murle) {
             System.out.println();
             System.out.println("MalformedURLException");
             System.out.println(murle);
             murle.printStackTrace();
       catch (RemoteException re) {
            System.out.println();
         System.out.println("RemoteException");
         System.out.println(re);
         re.printStackTrace();
       catch (NotBoundException nbe) {
         System.out.println();
         System.out.println("NotBoundException");
         System.out.println(nbe);
      return tt;
    public String updateTimetable(int id, String year, String group, String day, String time, String room, String lecturer, String subject){
           if (System.getSecurityManager() == null) {
                        System.setSecurityManager(new RMISecurityManager());
           try {
                 DBAdminInterface db = (DBAdminInterface) Naming.lookup ("rmi://Niall/DBAdmin");
                   result = db.updateTimetable(id, year, group, day, time, room, lecturer, subject);
                     catch (MalformedURLException murle) {
                        System.out.println();
                        System.out.println(
                          "MalformedURLException");
                        System.out.println(murle);
                    catch (RemoteException re) {
                        System.out.println();
                        System.out.println(
                                    "RemoteException");
                        System.out.println(re);
                    catch (NotBoundException nbe) {
                        System.out.println();
                        System.out.println(
                                   "NotBoundException");
                        System.out.println(nbe);
             return result;
}Im at a lose to what the problem is.
Cheers for any help.
N.

Answer 1

Ok i have used a LinkedList instead and created a class called Timetable myself to store the object info. Im now getting a serialverionnumber exception. I have implemented the same class in the client and server. What could be the problem?