I wanted to make a store management system using java Swing. Almost all done like employee addition, company addition, product addition etc, I am stuck with the bill portion. I am keeping another table for storing the bill details and now what i needed is to retrieve the data from bill table and print it. Could you please help me how to generate bill from DB and print it.

bill priview genaration code in java swing

import java.util.*;
class ebill
{
public static void main (String args[])
{
customerdata ob = new customerdata();
ob.Getdata();
ob.Calc();
ob.Display();

}
}

class customerdata
{
Scanner in = new Scanner (System.in);
Scanner ins = new Scanner (System.in);
String cname,fname;
int bn;
double units,tbill;

void Getdata()
{
System.out.print ("\n\t Enter block number = ");
bn = in.nextInt();
System.out.print ("\n\t Enter flate name = ");
fname = ins.nextLine();
System.out.print ("\n\t Enter customer name = ");
cname = ins.nextLine();
System.out.print ("\n\t Enter total consumed units = ");
units = in.nextDouble();
}

void Calc()
{
if (units<100)
tbill=0.40*units;
else if (units>100 && units<300)
tbill=0.50*units;
else
tbill=0.60*units;
if (tbill>150)
tbill+=tbill*0.15;
}

void Display()
{
System.out.println ("\n\t Customer name = "+cname);
System.out.println ("\n\t Total units = "+units);
System.out.println ("\n\t Total bill = RM "+tbill);
}
}