small correction :
public class SomeDao {
@SuppressWarnings("unchecked")
public Object getMetaData(Class clazz, long oid) {
Object o = em.find(clazz, oid);
return o;
}
..
}
CALLER:
Object o = someDao.getMetaData(Foo.class, 1);
---
regards
Marc Logemann
http://www.logemann.org
http://www.logentis.de
Am 03.12.2009 um 13:06 schrieb Marc Logemann:
> Hi,
>
> i am facing some weird performance issues. Given this JPA Query:
>
> public class SomeDao {
> @SuppressWarnings("unchecked")
> public Object getMetaData(Foo.class, long oid) {
> Object o = em.find(clazz, client);
> return o;
> }
> ..
> }
>
>
> @Entity
> @VersionColumn(name = "jpaversion")
> @Table(name = "foo")
> public class Foo extends BasicClientMetaData {
>
> @Id
> @Column(name = "client_oid")
> private long client;
> ...
> }
>
> @MappedSuperclass
> public class BasicClientMetaData implements MinMaxWeightAware {
>
>
> @Column(name = "custnr")
> private String customerNumber;
>
> @Column(name = "maxweight")
> private float maxWeightStandard;
> ..
> }
>
> When i call the getMetaData() of SomeDao.class (which is transactional and
> gets detached when its returned to the caller), i measured 500ms for this
> operation. The underlying SQL only consumes 20ms which i checked by setting
> the SQL log level to TRACE.
>
> Why is there such a difference? I mean, detaching cant be such an issue from
> performance perspective. I only have this issue with exactly these kind of
> classes (children of BasicClientMetaData).
>
> But i also have other classes which have the @MappedSuperclass which work
> without performance problems. Does anyone have a hint where i can look out
> for?
>
>
> thanks.
>
> ---
> regards
> Marc Logemann
> http://www.logemann.org
> http://www.logentis.de
>
>
>
>
