public <T> T findWithRole(String id, Class<T> role) {
Account account = findById(id);
if (!role.isAssignableFrom(account.getClass())) {
throw new NotFoundException();
}
return (T) account;
}
public Collection<Account> withRole(Class<?> role) {
ArrayList<Account> result = new ArrayList<Account>();
for (Account account : accounts.values()) {
if (role.isAssignableFrom(account.getClass())) {
result.add(account);
}
}
return result;
}