Exception "not implemented for class oracle.jdbc.driver.T4CNumberAccessor"

Question

Hello I'm having some troubles dealing with 'java.sql.Date' I'm working with express edition database and I have three classes(different packages)
1.Mapper
2.Objects Class
3.ConsoleTest
I need to get an arraylist of objects, some of which contain dates, but when try to do it I get this exception
"java.sql.SQLException: Invalid column type: getDate not implemented for class oracle.jdbc.driver.T4CNumberAccessor"
Do you have any idea how I can implement the getDate method for this T4CNumberAccessor
Here are the methods that I'm using
1.Mapper
public ArrayList<Object> getAllTaskAuctions(Connection con)
          ArrayList<Object> l1 = new ArrayList<Object>();
          String SQLString1 = "select * from taskauction natural join tasks";
PreparedStatement statement=null;
try
//=== get taskauctions natural join tasks
statement = con.prepareStatement(SQLString1);
ResultSet rs = statement.executeQuery();
while(rs.next())
l1.add(new TaskAuction(rs.getInt(1), rs.getInt(2), rs.getInt(3),
rs.getDate(4), rs.getDate(5), rs.getInt(6)));
l1.add(new Task(rs.getInt(1), rs.getInt(2), rs.getString(3),
rs.getString(4), rs.getString(5), rs.getString(6), rs.getInt(7)));
catch (Exception exc)
System.out.println("Fail in TaskAuctionMapper - getAllTaskAuctions");
System.out.println(exc);
return l1;
2.ConsoleTest class
Connection con;
     public Connection getConnection(){
          try{ 
     Class.forName("oracle.jdbc.driver.OracleDriver");
     con = DriverManager.getConnection(
     "jdbc:oracle:thin:@localhost:1521:XE", "Project", "123" );
     //username/password@[/]host[:port][service_name]
     catch (Exception e)
     {   System.out.println("fail in getConnection()");
     System.out.println(e); }
          return con;
     public static void main(String[] args) {
          ConsoleTest ct = new ConsoleTest();
          TaskAuctionMapper tam1 = new TaskAuctionMapper();
ArrayList<Object> alt1 = tam1.getAllTaskAuctions(ct.getConnection());
Iterator<Object> itr1 = alt1.iterator();
while (itr1.hasNext())
TaskAuction taskauct = (TaskAuction) itr1.next();
//Problem, exception traced to TaskAuctionMapper
System.out.println(
          "Task ID: " + taskauct.getTaskid()+ ", "+
          "StartDate: "+ taskauct.getStartdate()+", "+
          "User ID: " + taskauct.getUserid());
     }

Answer 1

Found the answer, I shouldn't use integers as parameters of column index in the result set, but instead use String to mark the fields :)