Hibernate Example OneToMany with compositeKey

hibernate, java, orm

Solution

I haven't done exactly what you are asking for but this might start you off in the right direction. I think it should work. This page explains these annotations in greater detail.

@Entity
public class Foo {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    public Long getId(){

    }
    ...
    @OneToMany(mappedBy="foo")
    public Collection<Bar> getBars() {

    }


...
}


@Entity
@IdClass(BarPk.class)
public class Bar implements Serializable {
    @ManyToOne
    @JoinColumn(name="foo")
    @Id
    public Foo getFoo() {
        return foo;
    }

    @Column(name="key", length=255)
    @Id
    public String getKey(){

    }

}


@Embeddable
public class BarPk implements Serializable {
    public Foo getFoo() {
        return foo;
    }
    public void setFoo(Foo foo) {

    }
    public String getKey(){
    ...
    }   

    public void setKey(String key){
    ...
    }     

    //you must include equals() and hashcode()    
}

Problem

Can you give me an example of a Hibernate mapping for the following situation: - Parent table(`foo`) with a simple primary key (`foo_id`) child table(`bar`) with a composite key consisting of a) Foreign key to parent table (`foo_id`) b) key(`item`) of type string - There is one parent to many child - The Parent class will have a list of Child objects - When a Parent class is saved, updated, deleted the changes will cascade to the Child

Original source