class Person{

private long id;
private Address address;
...

/**
* Returns the address.
* @hibernate.one-to-one name="getAddress" 
    class="foo.ejb.user.AddressBean"
*   cascade="all"
*   constrained="true"
* @return AddressBean
*/
public AddressBean getAddress() {
   return address;
}
}

class Address{

long id
...

/**
* Returns the id.
* @hibernate.id generator-class="foregin" type="long" column="id"
* unsaved-value="-1"
* @return long
*/
public Long getId() {
   return id;
}
}