/**
  * Deletes all Customer created by a given merchantId
  *
  * @param merchantId
  * @throws Exception
  */
 @Transactional
 public void deleteAllCustomers(int merchantId) throws Exception {
   Collection customers = getCustomerList(merchantId);
   if (customers != null && customers.size() > 0) {
     Iterator i = customers.iterator();
     while (i.hasNext()) {
       Customer customer = (Customer) i.next();
       deleteCustomer(customer);
     }
   }
 }