i make a customer object persistent

// create a new customer
customer = new Customers();

// fill with data
customer.setEmail(email);
customer.setPassword(password);

// make persistent
customersFacade.save(customer);

after persists i know the new id is in db 11, but if i log its 0
why it won*t set automattically
log.info("customer ID: " + customer.getCustomersId());

entity has this:

@Entity
@Table(name = "customers")
public class Customers implements Serializable {

// ------------------------------------------------------ Manifest Constants

private static final long serialVersionUID = 5L;

// ------------------------------------------------------- Public Properties

private long customersId;

private String firstName;

private String lastName;

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "customers_id")
public long getCustomersId() {
return customersId;
}

...

should work or how it works?