Simple OPAC Library Sytem in Java

//Event driven and the concurrent Program 
import java.sql.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
 public class Datas extends JFrame implements ActionListener
 { JTextField id;
JTextField name;
JButton next;
JButton addnew;
JPanel p;
static ResultSet res;
static Connection conn;
static Statement stat; 
public Datas(){
super("Our Application");
Container c = getContentPane();
c.setLayout(new GridLayout(5,1));
id = new JTextField(20);
name = new JTextField(20);
next = new JButton("Next BOOK");
p = new JPanel();
c.add(new JLabel("ISBN",JLabel.CENTER));
c.add(id);
c.add(new JLabel("Book Name",JLabel.CENTER));
c.add(name);
c.add(p);
p.add(next);
next.addActionListener(this);
pack();
setVisible(true);
addWindowListener(new WIN());
 }
 public static void main(String args[]) 
{
Datas d = new Datas();try {Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
 
conn = DriverManager.getConnection("jdbc:odbc:custo");
 // cust is the DSNName
stat = conn.createStatement();
res = stat.executeQuery("Select * from stu");
 // Customers is the table name
res.next();
 }
catch(Exception e) 
{System.out.println("Error" +e);
}
d.showRecord(res);
} 
public void actionPerformed(ActionEvent e)
 {
if(e.getSource() == next) 
{try 
{
res.next();
}catch(Exception ee)
 {
}
showRecord(res);
}
} 
public void showRecord(ResultSet res) 
{
try {
id.setText(res.getString(2));
name.setText(res.getString(3));
System.out.println("Book Id:"+res.getString(2)+"\nBookName:"+res.getString(3));
}catch(Exception e) {}
 }
//end of the main 
//Inner class WIN implemented
class WIN extends WindowAdapter 
{
public void windowClosing(WindowEvent w)
 {JOptionPane jop = new JOptionPane(); 
jop.showMessageDialog(null,"Database","Thanks",JOptionPane.QUESTION_MESSAGE);
}
 }
 } 

import java.sql.*;
import java.sql.DriverManager.*;
class Ja{
String bookid,bookname;int booksno;
Connection con;Statement stmt;
ResultSet rs;Ja(){try{Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con=DriverManager.getConnection("jdbc:odbc:custo");
}catch(Exception e){
System.out.println("connection error");
}
}
void myput()
{

try{
stmt=con.createStatement();
rs=stmt.executeQuery("SELECT * FROM stu");
System.out.println("\nbooksno\tbookid\tbookname");
while(rs.next())
{booksno=rs.getInt(1);
bookid=rs.getString(2);
bookname=rs.getString(3);
System.out.println("\n"+booksno+"\t"+bookid+"\t"+bookname);
}
rs.close();
stmt.close();
con.close();
}
catch(SQLException e)
{System.out.println("sql error");
}}}
class prog1{
 
public static void main(String arg[])
{Ja j=new Ja(); 
j.myput();
}
}