Hi,

I'm new to Hibernate and I'm having trouble creating 2 relationships between the same two classes. I can get both relationships working correctly independently, but when I try to combine them I'm getting errors.

Lets just say my first class is Items (for sale on an auction website) and my second class is Users

The first relationship is a OneToMany, since an Item for sale can have only one owner but a user can own many iterms

On User.java:

@OneToMany(mappedBy = "user")
public Set<Item> getOwnedItems(){
return ownedItems;
}

public void setOwnedItems(Set<Item> ownedItems){
this.ownedItems = ownedItems;
}

and on Item.java:

@ManyToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinColumn(name = "user_fk")
public User getOwner() {
return owner;
}

public void setOwner(User owner) {
this.owner = owner;
}

The second relationship between Item and User is many to many as I would like other Users to be able to register interest in an item thats for sale.

I've used the following specification for User.java:

@ManyToMany(cascade = { CascadeType.ALL }, mappedBy = "users", fetch = FetchType.EAGER)
public Set<Item> getItems() {
return items;
}

public void setItems(Set<Item> items) {
this.items = items; }

and then on Item.java:

@ManyToMany(
cascade={CascadeType.ALL}
)
@JoinTable( name="user_item", joinColumns={@JoinColumn(name="item_fk")},
inverseJoinColumns={@JoinColumn(name="user_fk")}
)
public Set<User> getUsers()
{return users;}

public void setUsers(Set<User> users)
{this.users = users;}

As it stands, hibernate isnt even creating my database. I'm getting the following error back from the server:

Error creating bean with name 'org.springframework.transaction.interceptor.TransactionAttributeSourceAdvisor': Cannot create inner bean '(inner bean)' of type [org.springframework.transaction.interceptor.TransactionInterceptor] while setting bean property 'transactionInterceptor'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)': Cannot resolve reference to bean 'transactionManager' while setting bean property 'transactionManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager' defined in class path resource [applicationContext-services.xml]: Cannot resolve reference to bean 'entityManagerFactory' while setting bean property 'entityManagerFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [applicationContext-services.xml]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: mappedBy reference an unknown target entity property: com.bm.model.Item.user in com.bm.model.User.ownedItems

If anyone could help me out with this, I'd really appreciate it. Thanks!

The mappedBy should be "owner" not "user".

That worked, thanks!