Joining tables with composite keys in a legacy system in hibernate
- by Steve N
Hi,
I'm currently trying to create a pair of Hibernate annotated classes to load (read only) from a pair of tables in a legacy system. The legacy system uses a consistent (if somewhat dated) approach to keying tables. The tables I'm attempting to map are as follows:
Customer CustomerAddress
-------------------------- ----------------------------
customerNumber:string (pk) customerNumber:string (pk_1)
name:string sequenceNumber:int (pk_2)
street:string
postalCode:string
I've approached this by creating a CustomerAddress class like this:
@Entity
@Table(name="CustomerAddress")
@IdClass(CustomerAddressKey.class)
public class CustomerAddress {
@Id
@AttributeOverrides({
@AttributeOverride(name = "customerNumber", column = @Column(name="customerNumber")),
@AttributeOverride(name = "sequenceNumber", column = @Column(name="sequenceNumber"))
})
private String customerNumber;
private int sequenceNumber;
private String name;
private String postalCode;
...
}
Where the CustomerAddressKey class is a simple Serializable object with the two key fields. The Customer object is then defined as:
@Entity
@Table(name = "Customer")
public class Customer {
private String customerNumber;
private List<CustomerAddress> addresses = new ArrayList<CustomerAddress>();
private String name;
...
}
So, my question is: how do I express the OneToMany relationship on the Customer table?
