public void customerSorting() {
    for (int p = 0; p < this.customer.size(); p++) {
      Customer customer1 = this.customer.get(p);

      for (int i = 0; i < this.customer.size(); i++) {

        Customer customer2 = this.customer.get(i);
        int compare = customer1.compareTo(customer2);
        if (compare % 10 < 2) {
          int customer1Index = this.customer.indexOf(customer1);
          this.customer.remove(i);
          this.customer.add(i, customer1);
          this.customer.remove(customer1Index);
          this.customer.add(customer1Index, customer2);
          customer1 = customer2;
        }
      }
    }
  }