example of a while loop that simply prints out the numbers 1, 2, 3, 4, 5:

 

import java.util.Scanner;
public class BSIT
{
    public static void main(String[] args)
    {
        Scanner readme = new Scanner(System.in);

        int number;   // The number to be printed.

        number = 1;   // Start with 1.

        while ( number < 6 )
        {  // Keep going as long as number is < 6.

            System.out.println(number);

            number = number + 1;  // Go on to the next number.
        }

        System.out.println("Done!");

    }

}