*/
@CommandHandler
public void handle(RegisterAddressCommand command) {
Assert.notNull(command.getContactId(), "ContactIdentifier may not be null");
Assert.notNull(command.getAddressType(), "AddressType may not be null");
Address address = new Address(command.getStreetAndNumber(), command.getZipCode(), command.getCity());
Contact contact = repository.load(command.getContactId());
contact.registerAddress(command.getAddressType(), address);
}