/* Author: Stephanie Elzer
 * Date: February 2, 2007
 * Purpose: To demonstrate using the Random class to generate a pseudorandom phone number
 * 	Solving programming exercise #3 from Chapter 3
 */
import java.util.*;
import java.text.*;

public class Phone {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		
		// Declare a Random variable, generator, and instantiate the object
		Random generator = new Random();
		
		// Declare several int variables to hold the generated numbers
		int num1, num2, num3, middle, last;
		
		// The first three numbers in the phone number must be digits 0-7 (no 8s or 9s)
		num1 = generator.nextInt(8);
		num2 = generator.nextInt(8);
		num3 = generator.nextInt(8);
		
		// Middle number cannot be greater than 742.  In order to ensure that there
		// are three digits, set a minimum value of 100.  Generate a value between
		// 0 and 642, then add 100 to shift the range
		middle = generator.nextInt(643) + 100;
		
		// No restrictions on the last 4 digits.  However, we take a slightly different
		// approach to making sure that there are 4 digits.  We generate a number between
		// 0 and 9999, then use the DecimalFormat class with a pattern of 4 0s to make
		// sure that leading zeros are included.
		last = generator.nextInt(10000);
		DecimalFormat fmt = new DecimalFormat("0000");
		
		// Concatenating all of the generated values and displaying the phone number
		System.out.println("Phone number:" + num1 + num2 + num3 + "-" + middle + "-" +  fmt.format(last));
		
	}

}