Random-Format Number? Pls advise

[jay lai]

I display the random number works so far just print out the random number, and make it positve.
Please advise
1. How do I format to get xxx-xxx-xxxx
2. How do I get the first set not including 8 , 9 and the sum of 3 digit in the second set < 742.
Your help is greatly appreciated.
-----------------------------------------------------------
import java.util.Random;
import java.text.*;
public class Telephone
{
public static void main (String [] args)
{
Random generator = new Random ();
int num , formatNum, num2;
num = generator.nextInt();
//formatNum = Math.abs(num);
NumberFormat nf = NumberFormat.getInstance();
num2 = nf.parse(formatNum);

System.out.println ("A random telephone number is " + num2);
}
}

[Chris De Vries]

You can generate each number in the sequence by itself, and then output the sequence in any format you want. For example:

Random generator = new Random ();
// Area codes should include 0-7 according to description
int ac1 = generator.nextInt(8);
int ac2 = generator.nextInt(8);
int ac3 = generator.nextInt(8);
// second set the sum of digits should be less than 742, but
// 9+9+9 = 27, so the sum will always be less than 742
int pr1 = generator.nextInt(10);
int pr2 = generator.nextInt(10);
int pr3 = generator.nextInt(10);
// Final set is anything goes, can generate whole thing at once:
int fin = generator.nextInt(10000);

Formatting the individual digits is easy, but the four digit sequence might be less that 1000, so you need to ensure a minimum of four digits. Use java.text.NumberFormat for that:

NumberFormat nf = NumberFormat.getIntegerInstance();
nf.setGroupingUsed(false);
nf.setMinimumIntegerDigits(4);
nf.setMaximumIntegerDigits(4);
String finstr = nf.format(fin);

I hope this is helpful.
Chris

[jay lai]

Thanks Chris, it works