Child and Parent Saving On Null and Not Null

[Eric Juneau]

I have an object called Person. In the database table for person, there's a person_id (primary key) and parent_id. This parent_id refers to another person in the table, so a person can be the parent of another person, or not a parent at all.

When I try and save a Person where parentPerson is a null value, I get this error: non-transient entity has a null id

When I try and save a Person with a non-null parent, it does seem to save correctly, but I get this error: org.apache.cxf.interceptor.Fault: EL1008E:(pos 10): Field or property 'parentId' cannot be found on object of type 'com.mypackage.package.Person'

I'm not especially savvy on the hibernate keywords, so what do I need to change to help this along?

PersonServiceImpl.java

@Override
@CachePut(value = CacheNames.PERSON, key = "#person.id")
@CacheEvict(value = CacheNames.PERSON, key = "#person.parentId", condition = "#person.parentId != null")
public Person savePerson(Person person) throws BusinessException {
    ...
}

Person.java

@Entity
@Table(name = "PERSON")
@DiscriminatorValue("PERSON")
@PrimaryKeyJoinColumn(name = "PERSON_ID")
public class Person {
   ...
   @ManyToOne
   @JoinColumn(name = "PARENT_ID", referencedColumnName = "PERSON_ID")
   private Person parentPerson;
   ...
}