Hibernate: Annotation many-to-many (join table)

Bidirectonal many-to-many (join table) association

Hibernate Doc (Chap 8.5.3)


::Relationship::
person(many) <-> address(many)

::DB Schema::
person(personId)
address(addressId)
personaddress(personId, addressId)

::Java Operation::
person.getAddresses();
address.getPeople();

::Annotation::

@Entity
@Table(name = "PERSON")
public class Person {

  @Id
  @GeneratedValue(strategy = GenerationType.AUTO)
  @Column(name = "personId")
  private int id;

  // mapping owner
  @ManyToMany
  @JoinTable(name = "PersonAddress",
    joinColumns = {
      @JoinColumn(name="personId", unique = true)           
    },
    inverseJoinColumns = {
      @JoinColumn(name="addressId")
    }
  )
  private Set<Address> addresses;
}

@Entity
@Table(name = "ADDRESS")
public class Address {

  @Id
  @GeneratedValue(strategy = GenerationType.AUTO)
  @Column(name = "addressId")
  private int id;

  @ManyToMany(mappedBy="addresses")  // map info is in person class
  private Set<Person> people;
}

::Generated SQL::
- person.getAddresses();
select addresses0_.personId as personId1_, addresses0_.addressId as addressId1_, address1_.addressId as addressId3_0_ from PersonAddress addresses0_ left outer join ADDRESS address1_ on addresses0_.addressId=address1_.addressId where addresses0_.personId=?

- address.getPeople();
select people0_.addressId as addressId1_, people0_.personId as personId1_, person1_.personId as personId2_0_ from PersonAddress people0_ left outer join PERSON person1_ on people0_.personId=person1_.personId where people0_.addressId=?

[Association Mapping List]