Auto no generator using java mysql

This tutorial which help you to generating auto no using java and mysql.

Establish the database Connection

   public void Connect()
    {
        try {
            Class.forName("com.mysql.jdbc.Driver");
            con = DriverManager.getConnection("jdbc:mysql://localhost/gshop","root","");
        } catch (ClassNotFoundException ex) {
        
        } catch (SQLException ex) {
            
        }   
    }

Auto no generator.create the function Custno().

 public void CustNo()
    {
         int custno =  1;
        try {
           
            Statement smt = con.createStatement();
          
            ResultSet rs = smt.executeQuery("select count(distinct customerid)+1 from records");
            rs.next();
            custno = rs.getInt(1);          
            txtno.setText("C000"+custno);
            
            rs.close();
            
            
            
        } catch (SQLException ex) {
            
        }
        
      
        
    }

Add Records. after add the record Customer no will be incremented by 1

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

        try {

            String cno = txtno.getText();
            String cname = txtname.getText();

            pst = con.prepareStatement("insert into records(customerid,custname)values(?,?)");
            pst.setString(1, cno);
            pst.setString(2, cname);

            int status = pst.executeUpdate();
            
            if(status==1)
            {
                JOptionPane.showMessageDialog(this, "New Customer Addedd");
                 CustNo();
                 txtname.setText("");
                 txtname.requestFocus();

            }
            else
            {
                JOptionPane.showMessageDialog(this, "New Customer Addedd Failedddd!!!");
            }
            
            
            
        } catch (SQLException ex) {
           
        }
        
        
        
    }