Hi,
I am stuck with a big problem that involves a one-to-many
relationship, the jdo mapping (done via xml-metadata) and the index I
have to create to mantain an order ..
Here it is the main class:
public class Album {
[..]
protected List<Media> medias = null;
[..]
}
.. then the JDO mapping:
<field persistence-modifier="persistent" name="medias" mapped-
by="album">
<collection dependent-element="true"
element-type="Media"></
collection>
<order />
</field>
.. and then the index (in datastore-indexes.xml) to mantain the order:
<datastore-index kind="Media" ancestor="true" source="manual">
<property name="medias_INTEGER_IDX" direction="asc"/>
</datastore-index>
.. now "sometimes" I get this error:
Class "it.icaroproject.main.model.Album" has collection field "medias"
and this has no mapping in the table for the index of the element
class "it.icaroproject.main.model.Media". Maybe you declared the field
as a java.util.Collection and instantiated it as a java.util.List yet
omitted the <order> element in the MetaData ?
org.datanucleus.exceptions.NucleusUserException: Class
"it.icaroproject.main.model.Album" has collection field "medias" and
this has no mapping in the table for the index of the element class
"it.icaroproject.main.model.Media". Maybe you declared the field as a
java.util.Collection and instantiated it as a java.util.List yet
omitted the <order> element in the MetaData ?
I really don't understand what's happening .. And it's strange because
after having re-deployed sometimes it works .. It's even more strange
because I have another one to many mapping similar to this one and it
works without any problems ..
So no fixed steps to reproduce and apparently no mistakes in the
code ..
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