I have a sample with entity inheritance (by the way: just a sample to show 
inheritance, nothing which makes sense ;-) ): one base class 
(ZutatBaseInheritanceBean with generated id and one field), three child classes 
(ZutatGewichtInheritanceBean, ZutatFluessigkeitInheritanceBean, 
ZutatStueckzahlInheritanceBean).

I want to make it running in all three inheritance strategies. SINGLE_TABLE und 
JOINED work fine. But for TABLE_PER_CLASS, it fails to populate a collection of 
all entities. The first type (ZutatGewichtInheritanceBean) is properly 
initialized, the other two types just contain the base class fields, all their 
individual fields are empty.

The named query to load all types of child entities is:
@NamedQuery (name="findAllZutaten", query="select o from 
ZutatBaseInheritanceBean o")

This seems to be a matter of the SQL statement which I see in the console:
select zutatbasei0_.id as id113_, zutatbasei0_.kuchen_id as kuchen3_113_, 
zutatbasei0_.zutatName as zutatName113_, 
  | zutatbasei0_.gewicht as gewicht114_, zutatbasei0_.gewichtEinheit as 
gewichtE2_114_, 
  | zutatbasei0_.masseinheit as masseinh1_115_, zutatbasei0_.masseinheitMenge 
as masseinh2_115_, 
  | zutatbasei0_.anzahl as anzahl116_, zutatbasei0_.clazz_ as clazz_ from 
  | ( select id, gewicht, zutatName, null as anzahl, kuchen_id, null as 
masseinheit, gewichtEinheit, null as masseinheitMenge, 1 as clazz_ from 
ZutatGewichtInheritanceBean union select id, null as gewicht, zutatName, null 
as anzahl, kuchen_id, masseinheit, null as gewichtEinheit, masseinheitMenge, 2 
as clazz_ from ZutatFluessigkeitInheritanceBean union select id, null as 
gewicht, zutatName, anzahl, kuchen_id, null as masseinheit, null as 
gewichtEinheit, null as masseinheitMenge, 3 as clazz_ from 
ZutatStueckzahlInheritanceBean ) zutatbasei0_ 
The columns from ZutatFluessigkeitInheritanceBean and 
ZutatStueckzahlInheritanceBean are always NULL, so I suspect that either 
Hypersonic does not support it or the EntityManager creates a wrong query.

I have a "working" sample at 
http://www.informatik.fh-wiesbaden.de/~knauf/KomponentenArchitekturen2008/kuchenzutatinheritance/KuchenZutatInheritance.ear,
 but it is completely in german, and the app client is a bit difficult to start 
(uses EJB injection), so I hope someone can make sense of my descriptions ;-).

I had a similar sample with two child classes, which worked in JBoss 4.2. If I 
find the time, I will test it with JBoss 5.

Thanks

Wolfgang

View the original post : 
http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4190271#4190271

Reply to the post : 
http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4190271
_______________________________________________
jboss-user mailing list
[email protected]
https://lists.jboss.org/mailman/listinfo/jboss-user

Reply via email to