Sorry but when I look this :
<class-descriptor class="B" table="B">
<field-descriptor name="id" column="ID" jdbc-type="INTEGER" primarykey="true"
autoincrement="true"/>
<field-descriptor name="email" column="EMAIL" jdbc-type="VARCHAR"/>
<reference-descriptor name="super" class-ref="A">
<foreignkey field-ref="id"/>
</reference-descriptor>
</class-descriptor>
I think your class is like this :
class B
{
private int id;
private String email;
private A super;
/* getters and setters*/
}
So, it's an agregation (also extends but where is your type A attribute in B ?) and
you can add criteria("B.super",null)
Not sure to understand your goal ...
----- Original Message -----
From: shibin ck
To: OJB Users List
Sent: Friday, September 12, 2003 11:38 AM
Subject: Inheritance querying problem
Hi,
i have 2 classes A and B. B inherits from A. i map classes A and B on multiple
joined tables.
my classes are
class A
{
private int id;
private String name;
/* getters and setters*/
}
class B extends A
{
private int id;
private String email;
/* getters and setters*/
}
my descriptor file is like
<class-descriptor class="A" table="A">
<field-descriptor name="id" column="ID" jdbc-type="INTEGER"
primarykey="true" autoincrement="true"/>
<field-descriptor name="name" column="NAME" jdbc-type="VARCHAR"/>
</class-descriptor>
<class-descriptor class="B" table="B">
<field-descriptor name="id" column="ID" jdbc-type="INTEGER"
primarykey="true" autoincrement="true"/>
<field-descriptor name="email" column="EMAIL" jdbc-type="VARCHAR"/>
<reference-descriptor name="super" class-ref="A">
<foreignkey field-ref="id"/>
</reference-descriptor>
</class-descriptor>
The problem is when i query on A class with null criteria .. it returns objects of A
only
ie
QueryByCriteria queryOne = new QueryByCriteria (A.class, null);
Collection col = broker.getCollectionByQuery (queryOne);
Iterator iter = col.iterator ();
while (iter.hasNext ())
{
System.out.println(iter.next().getClass());
}
this prints class A only ... (i'm getting B objects as A objects so i am able to get
name of B objects but not email) ..
If i use each class in separate table (with <extent> tag) ... it is working fine
(class A and class B are printing)
So my question is
is there any way by which we can get child attributes by quering on parent class
using <reference-descriptor name="super" ... method???
Thanks in advance
shibin
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