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Hibernate version:hibernate-annotations-3.1beta8

I am having difficulty trying to map an entity which contains a parent entity and collection of children entities of the same class type using annotations. Basically, I want to create a tree of parent-children entities using the example below:

@Entity
@Table(name = "T_ORGANIZATION")
public class Organization implements IOrganization, java.io.Serializable {

private Long _id = null;
private String _name = null;
private IOrganization _parent = null;
private ArrayList<IOrganization> _children = null;

public Organization() {
_children = new ArrayList<IOrganization>();
}

public void setId(Long id) {
_id = id;
}

@Id
@GeneratedValue
@Column(name = "ORG_ID")
public Long getId() {
return _id;
}

public void setName(String name) {
_name = name;
}

@Column(name = "ORG_NAME")
public String getName() {
return _name;
}

public void setParent(IOrganization parent) {
_parent = parent;
}

@OneToOne(cascade = CascadeType.ALL, targetEntity = Organization.class)
@JoinColumn(name="PARENT_ID")
public IOrganization getParent() {
return _parent;
}

public void setChildren(Collection<IOrganization> children) {
_children = new ArrayList<IOrganization>(children);
}

@OneToMany(cascade=CascadeType.ALL, fetch=FetchType.LAZY, targetEntity=Organization.class)
// HOW DO I JOIN THIS???
public Collection<IOrganization> getChildren() {
return _children;
}
}


TABLE T_ORGANIZATION:
+----------------+------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------------+------------------+------+-----+---------+----------------+
| ORG_ID | int(10) unsigned | NO | PRI | NULL | auto_increment |
| PARENT_ID | int(10) unsigned | YES | | NULL | |
| ORG_NAME | varchar(50) | YES | | NULL | |
+----------------+------------------+------+-----+---------+----------------+

How do I go about mapping the child relationships when I just want to keep the parent child relationships in the same table? The parent reference will work for me, but am having difficulty storing and fetching the children.

Try this, though I am not sure if it will work with interfaces:


I just tried it and it seems to work. The IOrganization interface that I created already extends Serializable so I didn't make Organisation implement it.
Hope it helps!