Going crazy.. can't join on this compound key class and not sure why?

[Brick Riccardi]

I have a compound Primary Key and I created an object to represent that Primary Key. What I'm curious about is how I can join on a member property of that primary key object if I so desire.

For example this named query is not working:

select ap from AssociatePreference ap, Associate ass where ass.associateID = ap.pk.associateID and ass.dmzID = :dmzID

The error:

    
findByDmzId(com.foobar.ondp.persistence.model.AssociatePreferenceTest)  Time elapsed: 0.01 sec  <<< FAILURE!
java.lang.IllegalArgumentException: node to traverse cannot be null!
  at org.hibernate.hql.ast.util.NodeTraverser.traverseDepthFirst(NodeTraverser.java:31)
  at org.hibernate.hql.ast.QueryTranslatorImpl.parse(QueryTranslatorImpl.java:254)
  at 
... 

I'm not sure why I can't query on that kind of join, there should be a way since it's so darn simple in sql. I understand I can actually get the AssociatePreference List by going after the Associate record - that'll work fine - however there 'should' be a way I can just get AssociatePreferene objects trying a join in some way without caring about the entire Associate.

I've posted relevant portions of code below:

@Entity
@Table(name = "NPPAssociatePreference")
@NamedQueries({
     @NamedQuery(name="AssociatePreference.byDmzID", query="select ap from AssociatePreference ap, Associate ass where ass.associateID = ap.pk.associateID and ass.dmzID = :dmzID")
})
public class AssociatePreference extends BaseEntity {
 
 
private AssociatePreferencePK pk; 
private String value;  
 
public String getValue() {
    return value;
}
 
public void setValue(String value) {
    this.value = value;
}
 
@EmbeddedId
public AssociatePreferencePK getPk() {
    return pk;
}
 
public void setPk(AssociatePreferencePK pk) {
    this.pk = pk;
}
}
 
 
@Embeddable
public class AssociatePreferencePK extends BasePK {
 
    private int associateID;  
    private int preferenceID;
 
    public AssociatePreferencePK() {
        super();
    }
    
    public AssociatePreferencePK(int associateID, int preferenceID ) {
        this.associateID = associateID;
        this.preferenceID = preferenceID; 
    }
    
 
    @Column(nullable=false)
    public int getAssociateID() {
        return associateID;
    }
    
    public void setAssociateID(Integer associateID) {
        this.associateID = associateID;
    }
    
    @Column(nullable=false)
    public int getPreferenceID() {
        return preferenceID;
    }
    
    public void setPreferenceID(Integer preferenceID) {
        this.preferenceID = preferenceID;
    } 
}
 
@Entity
@Table(name = "NPPAssociate")
public class Associate extends BaseEntity { 
 
    private int associateID;
    private Set<AssociatePreference> associatePreferences;
    //many more properties
 
    @Id
    @Column(nullable=false, unique=true)
    public Integer getAssociateID() {
        return this.associateID;
    }
 
    @OneToMany(fetch=FetchType.LAZY, cascade=CascadeType.REMOVE)
    @JoinColumn(name="associateID")
    public Set<AssociatePreference> getAssociatePreferences() { 
        return this.associatePreferences;
    }
    ....
}

edited bc forgot to disable smilies
[ October 27, 2008: Message edited by: Brick Riccardi ]