private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {

   String username=jTextField1.getText();
   String password=jPasswordField1.getText();
   String new_pass=jPasswordField2.getText();
   update(1,username,new_pass);
}

public void update(int id, String name, String pass) {

    int i = 0;
    try {
        Class.forName("com.mysql.jdbc.Driver");
        Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/database", "root", "");

        String sql = "UPDATE user_pass SET id=?, password=? WHERE username=? ";
        PreparedStatement pst = con.prepareStatement(sql);
        pst.setInt(1, id);
        System.out.println("Yeha samma thik xa");
        pst.setString(2, name);
        pst.setString(3, pass);
        pst.executeUpdate();
        System.out.println("Updated Successifully");
        JOptionPane.showMessageDialog(null, "Successifully updated! ");

    } catch (Exception ex) {
        JOptionPane.showMessageDialog(null, "Sorry there is an errornPlease check the information provided  ", " ", JOptionPane.ERROR_MESSAGE);
    }

}

catch (Exception ex) {
    JOptionPane.showMessageDialog(null, "Sorry there is an errornPlease check the information provided  ", " ", JOptionPane.ERROR_MESSAGE);
}

String sql=UPDATE user_pass SET id='"+id+"', password='"+password+"' WHERE username='"+username+"' ";

} catch (Exception ex) {