How to make this with hibernate annoations

ppareit · **Joined:** Fri Nov 11, 2005 4:35 pm **Posts:** 23

Hi,

I need to make two hibernate beans of the following ERD:

Any suggestions?

Thanks,
Pieter

Cameron McKenzie · **Posted:** Mon Aug 10, 2009 7:14 am

This simply looks like a mapping of a compound key for each table first, and then a one-to-many association, right?

Mapping Compound Primary Keys Tutorial:
http://jpa.ezhibernate.com/Javacode/lea ... rimarykeys

Mapping One to One Relationships with Hibernate Tutorial:
http://jpa.ezhibernate.com/Javacode/lea ... sociations

Just curious - does effective date need to be part of a compound key?

ppareit · **Joined:** Fri Nov 11, 2005 4:35 pm **Posts:** 23

Hi Cameron,

Unfortunately effective date needs to be in the primary key.
This is how Oracle HCM stores historical data.

For the moment i'm this far:

Code:

@Entity
@IdClass(CompanyEffDatePK.class)
@Table(name = "COMPANY")
public class CompanyEffDate implements EffDateInterface
{
   // ----- CONSTANTS -----
   private static final long serialVersionUID = 6055686640986901623L;

   // ----- MEMBERS -----
   private String companyId;
   private Date effDate;
   
   private String name;

   // ----- GETTER -----
   
   /**
    * @return the companyId
    */
   @Id()
   @Column(name="ID")
   public String getCompanyId()
   {
      return companyId;
   }

   /**
    * @return the effDate
    */
   @Id()
   @Column(name="EFFDT")
   public Date getEffDate()
   {
      return effDate;
   }
...

Code:

@Entity
@IdClass(AddressEffDatePK.class)
@Table(name = "COMPANY_ADDRESS")
public class AddressEffDate implements EffDateInterface
{
   // ----- CONSTANTS -----
   private static final long serialVersionUID = -3827054467502810838L;
   
   // ----- MEMBERS -----
   private String addressId;
   private Date effDate;
   
   private String companyId;
   
   private String name;
   private String street;

   // ----- GETTER -----
   
   /**
    * @return the addressId
    */
   @Id()
   @Column(name="ID")
   public String getAddressId()
   {
      return addressId;
   }

   /**
    * @return the effDate
    */
   @Id()
   @Column(name="EFFDT")
   public Date getEffDate()
   {
      return effDate;
   }

   /**
    * @return the companyId
    */
   @Column(name="COMPANY_ID")
   public String getCompanyId()
   {
      return companyId;
   }
....

You see I can’t navigate between mappings.

Pieter

thatmikewilliams · **Posted:** Mon Aug 10, 2009 9:24 am

You simply need to define a one to many on the company class:

Code:

    @OneToMany(targetEntity=AddressEffDate.class)
    @JoinColumns({
        @JoinColumn(name="COMPANY_ID", referencedColumnName = "ID"),
        @JoinColumn(name="EFFDT", referencedColumnName = "EFFDT")})
   public List<AddressEffDate> getAddresses() {
      return addresses;
   }
   public void setAddresses(List<AddressEffDate> addresses) {
      this.addresses = addresses;
   }

ppareit · **Joined:** Fri Nov 11, 2005 4:35 pm **Posts:** 23

@JoinColumn(name="EFFDT", referencedColumnName = "EFFDT")})
AddressEffDate hasn't got the company EFFDT, it has a column EFFDT but it is related to the companyAddress

thatmikewilliams · **Posted:** Mon Aug 10, 2009 10:39 am

If the date is part of the primary key I assume when company data changes that a new row gets inserted into the company table with the same ID but a different date. If this is the case then the ERD is wrong and the relationship is many to many. Could be why you're having difficulty mapping it.