Cyclic Redundancy Check(CRC)

import java.util.Scanner;
class CRC{
    static String appendZeros(int n){ //append n zeros
        String str = "";
        for(int i = 0; i < n; i++) str += "0";
        return str;
    }
    static String removeZeros(String str){
        String result = "";
        for(int i = 0; i < str.length(); i++)
            if(str.charAt(i)=='1' && i!=0){
                result = str.substring(i);
                break;
            }
        return result;
    }
    static String exor(String a, String b){ //exor binary strings a and b
        String result = "";
        for(int i = 0; i < a.length(); i++)
            if(a.charAt(i) == b.charAt(i)) result += "0";
            else result += "1";
        return removeZeros(result);
    }
    static String getRemainder(String dividend, String divisor){//dividend%divisor
        String current = "";
        for(int i = 0; i < dividend.length(); i++){
            current += dividend.charAt(i);
            if(current.length() < divisor.length()) continue;
            else current = exor(current, divisor);
        }
        return appendZeros(divisor.length()-current.length()-1)+current;
    }
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a binary message: ");
        String message = sc.next();
        System.out.print("Enter a generator polynomial(in binary): ");
        String divisor = sc.next();
        String remainder = getRemainder(message+appendZeros(divisor.length()-1), divisor);
        System.out.println("The string transmitted will be "+message+""+remainder);
        if(Integer.parseInt(getRemainder(message+remainder, divisor)) == 0) System.out.println("Success.");
        else System.out.println("Faliure.");
    }
}