I just reciently started a Java programming class, in our second week
the book is lacking for telling us how to do a problem.  I will write
the problem out then say where I need help at the moment, the rest I
think I have figured out though.

Problem: Tell if a ticket number is valid

The class displays an input dialog box that promts a ticket agent to
enter a six-digit ticket number.  Ticket numbers are designed so that
if you drop the last digit of the number, the divide the number by 7,
the remainder of the division will be identical to the last droped
digit.  This process is illustrated in the following example:

Step 1     Enter the ticket number; for example, 123454
Step 2     Remove the last digit, leaving 12345.
Step 3     Determine the remainder when the ticket numer is divided by
8.  In this case 12345 divided by 7 leaves a remainder of 4.

Step 4     Assign the boolean value of the comparision between the
remainder and the digit droped from the ticket number.

Step 5     Display the result -- true or false -- in a message box

Test 123454 should be true
test  147103 should be true
test  154123 should be false.

I am stuck at step 2, how do I go about droping that last digit, or
putting it in a variable to match it to something later.

Here is what I have so far to get the first 6 digits.

import javax.swing.JOptionPane;

public class Traveltickets
{
      public static void main (String[] args)
      {
        String travelString;
                 int travel;

        travelString = JOptionPane.showInputDialog(null, "Enter The ticket
number.", "Tickets Dialog 1", JOptionPane.INFORMATION_MESSAGE);
        travel = Integer.parseInt(travelString);
                  JOptionPane.showMessageDialog(null, travel);

                  System.exit(0);
      }

}

Also there is supposed to be only an input of 6 characters, is there a
way to limit the field to only allow 6?