Checking if a value is equal to another within a loop(java)

I need to do find values 10 different times or until the value of difference is found twice. Im not really sure how to break the loop if found.

Here goes the code:

public class Algorithm {
    private static int small; //global field so it is usable in zeros method

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        int number = 0;
        // object array to use collections class
        Integer [] digit = new Integer [4]; 
        // loop for handling 10 different numbers
        for (int index=0; index<10; index++){ 
            number = random();
            String smaller =""; String bigger=""; // strings used to display zeros/ easier processing 
            for (int i = 3; i >= 0; i--) {
                digit[i] = number % 10;
                number /= 10;   
            }
            // prints initial random number
            System.out.println(digit[0] + " " +digit[1] + " " + 
            digit[2]+ " "+ digit[3] + " Random Number");
            // sorts the digits increasingly
            Arrays.sort(digit);
            // adds the numbers to the smaller string
            for (int i=0; i                 smaller += digit[i]; 

            }
            // convert string to int
            int small = Integer.parseInt(smaller); 
            String zerosNr = null;
            zerosNr = zeros();
            System.out.printf(" smaller " +zerosNr, small );
            // Reverse sort order and adds results to bigger for displaying
            Arrays.sort(digit, Collections.reverseOrder());
            for (int i=0; i < digit.length; i++){
                bigger += digit[i];
            }
            int big = Integer.parseInt(bigger);

            System.out.println("bigger " + big);
            int difference = 0;
            int [] copy;
            copy = new int[11];
            difference = big - small;
            copy[index] = big - small;
            // here i tried to do it 
            System.out.println( index + " Difference "+ difference);
            if (difference == copy[index+1]) 
                break;
        }
    }
    //method that creates random numbers
    public static int random(){
        final int n = 9999;
        Random rad = new Random();
        int number = rad.nextInt(n);
        return number;

    }
    //method that adds zeros where necesarry to smaller
    public static String zeros(){
        String zerosNr = null;
            if (small < 1000)
                return " %04d\n ";
            else if (small < 100)
                return " %03d\n ";
            else 
                return " %02d\n ";

    }
}