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Posted to users@openjpa.apache.org by dt...@sparnord.dk on 2009/03/19 12:06:54 UTC

NullPointerException?

Hi,

I'm getting this exception:

org.apache.openjpa.persistence.PersistenceException: null
                 at 
org.apache.openjpa.jdbc.meta.FieldMapping.assertStrategy(FieldMapping.java:888)
                 at 
org.apache.openjpa.jdbc.meta.FieldMapping.isEagerSelectToMany(FieldMapping.java:717)
                 at 
org.apache.openjpa.jdbc.kernel.JDBCStoreManager.createEagerSelects(JDBCStoreManager.java:966)
                 at 
org.apache.openjpa.jdbc.kernel.JDBCStoreManager.select(JDBCStoreManager.java:914)
                 at 
org.apache.openjpa.jdbc.sql.SelectImpl.select(SelectImpl.java:867)

Where I'm trying to implement a bidirectional one-to-many mapping via a 
join table:

public class OdsMedarbejder {
...
    @ManyToOne
    @JoinTable(name = "ODS_AFDELINGMEDARBEJDER",
               joinColumns = @JoinColumn(name = "MEDSEQ", 
referencedColumnName = "MEDSEQ"),
               inverseJoinColumns = @JoinColumn(name = "ORGSEQ", 
referencedColumnName = "ORGSEQ"))
    private OdsAfdeling afdeling;
...
}

public class OdsAfdeling {
...
    @Id
    protected double ORGSEQ;

    @OneToMany(mappedBy = "afdeling")
    protected Set<OdsMedarbejder> medarbejdere;
...
}

Any ideas? 

Thanks,

-dennis

Vedr.: Re: NullPointerException?

Posted by dt...@sparnord.dk.
Hi,

Sorry, I should have mentioned, that yes the two classes are annotated as 
entities.

It seems the problem may have been related to me forgetting to på an 
@PersistenceUnit annotation on the class.

However, I have tried adressing the problem in the meantime by changing 
the relationship to be many-to-many. But for some reason this just leaves 
the collection as "null" in all circumstances, even though lazy fetching 
is used (by default).

Hmm - help appreciated :)

-dennis


David Beer <da...@googlemail.com> skrev den 19-03-2009 13:13:35:
> Hi
> 
> Are your classes declared as entities using the @Entity annotation at 
the
> top of the class file.

Re: NullPointerException?

Posted by David Beer <da...@googlemail.com>.
Hi

Are your classes declared as entities using the @Entity annotation at the
top of the class file.

Thanks

David

2009/3/19 <dt...@sparnord.dk>

> Hi,
>
> I'm getting this exception:
>
> org.apache.openjpa.persistence.PersistenceException: null
>                 at
>
> org.apache.openjpa.jdbc.meta.FieldMapping.assertStrategy(FieldMapping.java:888)
>                 at
>
> org.apache.openjpa.jdbc.meta.FieldMapping.isEagerSelectToMany(FieldMapping.java:717)
>                 at
>
> org.apache.openjpa.jdbc.kernel.JDBCStoreManager.createEagerSelects(JDBCStoreManager.java:966)
>                 at
>
> org.apache.openjpa.jdbc.kernel.JDBCStoreManager.select(JDBCStoreManager.java:914)
>                 at
> org.apache.openjpa.jdbc.sql.SelectImpl.select(SelectImpl.java:867)
>
> Where I'm trying to implement a bidirectional one-to-many mapping via a
> join table:
>
> public class OdsMedarbejder {
> ...
>    @ManyToOne
>    @JoinTable(name = "ODS_AFDELINGMEDARBEJDER",
>               joinColumns = @JoinColumn(name = "MEDSEQ",
> referencedColumnName = "MEDSEQ"),
>               inverseJoinColumns = @JoinColumn(name = "ORGSEQ",
> referencedColumnName = "ORGSEQ"))
>    private OdsAfdeling afdeling;
> ...
> }
>
> public class OdsAfdeling {
> ...
>    @Id
>    protected double ORGSEQ;
>
>    @OneToMany(mappedBy = "afdeling")
>    protected Set<OdsMedarbejder> medarbejdere;
> ...
> }
>
> Any ideas?
>
> Thanks,
>
> -dennis

Vedr.: Re: NullPointerException?

Posted by dt...@sparnord.dk.
Hi,

Unfortunately I'm restricted to using the version in WebLogic server 10.3. 
I think it's OpenJPA 1.0, but I'm not sure.

Could I upgrade the OpenJPA version in WLS in some non-invasive way?


Thanks,

-dennis


Paul Copeland <te...@jotobjects.com> skrev den 19-03-2009 16:36:33:
> 
> Which version of OpenJPA are you using?
> 
> 
> On 3/19/2009 4:06 AM, dth@sparnord.dk wrote:

Re: NullPointerException?

Posted by Paul Copeland <te...@jotobjects.com>.
Which version of OpenJPA are you using?


On 3/19/2009 4:06 AM, dth@sparnord.dk wrote:
> Hi,
>
> I'm getting this exception:
>
> org.apache.openjpa.persistence.PersistenceException: null
>                  at 
> org.apache.openjpa.jdbc.meta.FieldMapping.assertStrategy(FieldMapping.java:888)
>                  at 
> org.apache.openjpa.jdbc.meta.FieldMapping.isEagerSelectToMany(FieldMapping.java:717)
>                  at 
> org.apache.openjpa.jdbc.kernel.JDBCStoreManager.createEagerSelects(JDBCStoreManager.java:966)
>                  at 
> org.apache.openjpa.jdbc.kernel.JDBCStoreManager.select(JDBCStoreManager.java:914)
>                  at 
> org.apache.openjpa.jdbc.sql.SelectImpl.select(SelectImpl.java:867)
>
> Where I'm trying to implement a bidirectional one-to-many mapping via a 
> join table:
>
> public class OdsMedarbejder {
> ...
>     @ManyToOne
>     @JoinTable(name = "ODS_AFDELINGMEDARBEJDER",
>                joinColumns = @JoinColumn(name = "MEDSEQ", 
> referencedColumnName = "MEDSEQ"),
>                inverseJoinColumns = @JoinColumn(name = "ORGSEQ", 
> referencedColumnName = "ORGSEQ"))
>     private OdsAfdeling afdeling;
> ...
> }
>
> public class OdsAfdeling {
> ...
>     @Id
>     protected double ORGSEQ;
>
>     @OneToMany(mappedBy = "afdeling")
>     protected Set<OdsMedarbejder> medarbejdere;
> ...
> }
>
> Any ideas? 
>
> Thanks,
>
> -dennis
>