need help in corejava project

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Hi

I'm Riya a B.Tech. student and i have to make a corejava project on the topic COLLEGE MANAGEMENT SYSTEM . I have created the required database using MS Access. I m facing problem in a code which i m attaching here. Actually i want to update a data in the data base so i have made 2 frames in one of them Roll no. is asked when it is entered then the 2nd frame opens and asks Enter Marks to be updated...when i enter the marks to be updated then a dialogue box opens shoing "Marks Updated Successfully". Till here i don't have any problem..the problem is when i open the database i see that actually the Marks is not updated there.So please please please somebody help me solving this problem.

**The code is as follows:

!ST FRAME**

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;
class MyFrame03 extends JFrame implements ActionListener
{
JLabel l1;
JTextField t1;
JPanel p1,p2;
JButton b1;
Connection con;
PreparedStatement pst;
String s1;
MyFrame03()
{
setLayout(new GridLayout(4,1));
setTitle("Enter Data Required");
setBackground(Color.blue);
l1=new JLabel("Roll no");
t1=new JTextField(12);
p1=new JPanel();
p2=new JPanel();
b1=new JButton("SUBMIT");
p1.add(l1);
p1.add(t1);
p2.add(b1);
add(p1,"Center");
add(p2,"South");
b1.addActionListener(this);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400,500);
setVisible(true);
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con=DriverManager.getConnection("Jdbc:Odbc:dsn3");
if(con!=null)
System.out.println("Connection Established");
}
catch(Exception e)
{
System.out.println("exception");
}
}
public void actionPerformed(ActionEvent e1)
{
if(e1.getSource()==b1)
{
s1=t1.getText();
try
{
pst=con.prepareStatement("insert into stud values(?)");
pst.setString(1,s1);
pst.executeUpdate();
con.commit();
con.close();
}
catch(SQLException e)
{
System.out.println("except1");
}
MyFrame04 m1=new MyFrame04(s1);
dispose();
}
}
public static void main(String s[]) throws SQLException
{
MyFrame03 m1 =new MyFrame03();
}
}


2nd FRAME

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.sql.*;
class MyFrame04 extends JFrame implements ActionListener
{
JLabel l1;
JTextField t1;
JPanel p1,p2;
JButton b1;
String s1,s2;
Connection con;
PreparedStatement pst;
public MyFrame04(String s1)
{
this.s1=s1;
setLayout(new GridLayout(4,1));
setTitle("Update Marks");
setBackground(Color.blue);
l1=new JLabel("Enter Marks");
t1=new JTextField(12);
b1=new JButton("SUBMIT");
p1=new JPanel();
p2=new JPanel();
p1.add(l1);
p1.add(t1);
p2.add(b1);
add(p1,"Center");
add(p2,"South");
b1.addActionListener(this);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400,500);
setVisible(true);
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con=DriverManager.getConnection("Jdbc:Odbc:dsn3");
if(con!=null)
System.out.println("Connection Established");
}
catch(Exception e)
{
System.out.println("exception");
}
}
public void actionPerformed(ActionEvent e1)
{
if(e1.getSource()==b1)
{
s2=t1.getText();
try
{
pst=con.prepareStatement("UPDATE stud set Marks=? WHERE Roll no=?");
pst.setString(1,s2);
pst.setString(2,s1);
pst.executeUpdate();
con.commit();
con.close();
}
catch(SQLException e)
{
System.out.println("except1");
}
JOptionPane.showMessageDialog(this ,"Marks updated succesfully");
dispose();
}
}
}

Thankyou

 

see in console if any exception is occuring or not

write this line JOptionPane.showMessageDialog(this ,"Marks updated succesfully");
inside try block and check if it displaying it.

and change below code

catch(SQLException e)
{
System.out.println("except1");
}

to

catch(SQLException e)
{
System.out.println("except1: "+e);
}

to check what kind of exception has occured