By-directional one-to-many relations with Hibernate and annotations

If have a POJO User and Home. One user can have multiple homes, and homes should know their user. Thus, one user should have many homes, and homes have one owner. Since I ran into some trouble while doing this, this is a short example of what to do. Another simple example (in German) helped me to come to a correct solution

My POJOs look like:
If have a POJO User and Home. One user can have multiple homes, and homes should know their user. Thus, one user should have many homes, and homes have one owner. Since I ran into some trouble while doing this, this is a short example of what to do. Another simple example (in German) helped me to come to a correct solution

My POJOs look like:

@Entity
@Table(name=\"app_user\")
public class User implements Serializable {

   private Long id;
 
   private Set<Home> homes = new HashSet<Home>();
  
   /**
    * Default constructor - creates a new instance with no values set.
    */
   public User() {}

   @Id @GeneratedValue(strategy=GenerationType.AUTO)
   public Long getId() {
       return id;
   }
  
   @OneToMany(mappedBy=\"owner\")
   public Set<Home> getHomes()
   {
       return homes;
   }
  
   // setters, ...
}

and

@Entity @Table(name=\"home\")
public class Home extends BaseObject {

 private Long id;

 
   private User owner;
  
  
   @Id
   @GeneratedValue(strategy = GenerationType.AUTO)
   public Long getId() {
       return id;
   }

   @ManyToOne
   @JoinColumn(name=\"user_id\")
   public User getOwner() {
    return owner;
   }

   // setters, ...
}

The relationship is saved in Home in the property owner (Home.owner). The foreign key is saved in the field user_id of table home.

When you get the error

mappedBy reference an unknown target

this means that the mappedBy is not set correctly. Ensure that the target is set correctly -- in this scenario, mappedBy specifies field owner of class Home as target.