Have a challenge (at least to me) for a challenger

Question

i got a new screenname so i could give away the 25 dukes to whoever does it, not too sure if its much of an incentive. out of the past 48 hours i have been up about 40 of those hours, and i am so burned out on java right now i dont care about the stupid bet i did this for, but i know i do (know what i mean?!). anyway, i thought i'd let some very gracious and smart person(s) to help out a not-so-good rookie java programmer. i have already received help, and could always use more!! so, i have the first part of this program finished. all i need left to do is decrypt it. the instructions that were given to me are below (the decryption is the reverse of the instructions). the code i have is below that. i have case 1 finished, i just need the method for case 2. i appreciate whoever helps me out, it will be returned. thank u!!!! now im going to bed.
1. Swap digits 1 and 7, 2 and 6, and 3 and 5 of the original number
2. Using the output of phase 1, replace each digit with the sum of that digit plus 9 modulo 10
3. Using the output of phase 2, swap digits 1 and 2, 3 and 4, and 5 and 6
import javax.swing.*;
public class Program3{
public static int array;
public static void main( String args [ ] )
String num, num1, num2;
int number, number1, number2;
num = showMenu ( );
number = Integer.parseInt( num );
if( number < 4 )
switch ( number ){        
case 1:
num1 = JOptionPane.showInputDialog("Please enter a seven digit number : ");
number1 = Integer.parseInt( num1 );
swapDigit( num1 );
break;
case 2:
num2 = JOptionPane.showInputDialog("Enter an encrypted number : ");
number2 = Integer.parseInt( num2 );
break;
case 3:
System.exit ( 0 );
else
JOptionPane.showMessageDialog(null, "Enter another number. Choose ONLY numbers 1, 2, or 3 !!! GOT IT!!!\nGood, now let's try this again Einstein.", "HEY!!!!", JOptionPane.INFORMATION_MESSAGE);
showMenu ( );
public static String showMenu ( )
return JOptionPane.showInputDialog("Please enter the number corresponding to your choice : \n\n1. Encryption\n2. Decryption\n3. Exit\n");
public static void swapDigit ( String num1 )
int nums[ ] = new int[7];
char[ ] c = num1.toCharArray( );
int digit = 0;
for ( int k = 6; k >= 0; k--) {
nums [ digit++ ] = (Integer.parseInt (String.valueOf (c [ k ] )) + 9) % 10;
StringBuffer finaloutput = new StringBuffer( );
finaloutput.append( nums [1]);
finaloutput.append( nums [0]);
finaloutput.append(nums [3]);
finaloutput.append(nums [2]);
finaloutput.append(nums [5]);
finaloutput.append(nums [4]);
finaloutput.append(nums [6]);
array = Integer.parseInt( finaloutput.toString());
JOptionPane.showMessageDialog( null, finaloutput, "encrypted number", JOptionPane.INFORMATION_MESSAGE);

Answer 1

This site has problem with the posting of code...here is an unformatted version:
import javax.swing.*;
public class Program3 {
   public static int array;
   public static void main( String args [ ] ) {
      String num, num1, num2;
      int number=0;
      boolean repeat=true;
      while (repeat) {
      num = showMenu ();
      number = Integer.parseInt( num );
      if (number < 4 ) {
         switch (number ) {
            case 1:
               num1 = JOptionPane.showInputDialog("Please enter a seven digit number : ");
               num1=step1(num1);
               num1=step2(num1);
               num1=step3(num1);
               JOptionPane.showMessageDialog( null, num1, "encrypted number", JOptionPane.INFORMATION_MESSAGE);
               break;
            case 2:
               num2 = JOptionPane.showInputDialog("Enter an encrypted number : ");
               num2=step3(num2);
               num2=step2r(num2);
               num2=step1(num2);
               JOptionPane.showMessageDialog( null, num2, "decrypted number", JOptionPane.INFORMATION_MESSAGE);
               break;
            case 3:
               repeat=false;
               break;
      } else JOptionPane.showMessageDialog(null, "Enter another number. Choose ONLY numbers 1, 2, or 3 !!! GOT IT!!!\nGood, now let's try this again Einstein.","HEY!!!!",
           JOptionPane.INFORMATION_MESSAGE);
      System.exit (0 );
   public static String showMenu () {
      return JOptionPane.showInputDialog("Please enter the number corresponding to your choice : \n\n1. Encryption\n2. Decryption\n3. Exit\n");
   public static String step1(String num1) {
      String ret="";
      for (int i=6;i>=0;i--) ret+=num1.charAt(i);
      return ret;
   public static String step2(String num1) {
      String ret="";
      for (int i=0;i<7;i++) ret+=((num1.charAt(i)-'0') + 9) % 10;
      return ret;
   public static String step2r(String num1) {
      String ret="";
      for (int i=0;i<7;i++) ret+=((num1.charAt(i)-'0') + 10) % 9;
      return ret;
   public static String step3(String num1) {
      String ret="";
      ret+=num1.charAt(1);
      ret+=num1.charAt(0);
      ret+=num1.charAt(3);
      ret+=num1.charAt(2);
      ret+=num1.charAt(5);
      ret+=num1.charAt(4);
      ret+=num1.charAt(6);
      return ret;
}Better?
V.V.