Hi again Armin,
I saw some discussions regarding the AbstractIndirectionHandler class, maybe
the method "public Object invoke" is outdated in the OJB version in use by
me. I'm using OJB1.0.4 and the jar file date is 31/12/2005. Is that correct?
Is there any other version available? If so, please point me out where can I
get it.
Thank you!
Schmidt wrote:
>
> Hi Armin,
>
> Thank you for the answer.
>
> I'm using the 1.0.4 version. And the same problem happens with 1:n
> associations as well. In the 1:n associations I set auto-retrieve="false"
> and proxy="dynamic". As my classes do not implement interfaces, I'm using
> CGLib as ProxyFactoryClass.
> I debugged the source code and verified that the collection representing
> the n side of the 1:n association is filled with proxy references. That's
> good because the real object are not materialized, but when I check for
> nullity, the result is false due to proxy references. The solution (ugly)
> to bypass this problem is in the ProxyHelper.getRealObject method. But
> this solution is invasive, proxies should be transparent.
>
> Another problem that came up after I started using proxies is in the
> hierarchy mapping. I'm using just one table to map my class hierarchy. So,
> this table has a CLASSNAME field to identify which class to load. In the
> constructor of my base class I have a
> setOjbConcreteClass(this.getClass().getName()) call. Before using proxies,
> the class name was configured correctly. But after, instead of having the
> real object class name, the application configures the classname field
> using the proxy class name.
>
> I assume there should be something wrong with my mapping files or some
> other point in my application. As said earlier, I believe proxies should
> be transparent. Did someone here experience the same problems?
>
> Thank you again!
>
>
> Armin Waibel wrote:
>>
>> Hi,
>>
>> Schmidt wrote:
>>> Hi,
>>>
>>> Consider that an object A has an association with an object B. Also that
>>> dynamic proxies are in use so that when object A is loaded, a proxy to B
>>> is
>>> created and the object B itself is not materialized. Sometimes, before
>>> taking an action, I need to verify if there is a B object associated to
>>> A.
>>> This check is done as follows:
>>> if (a.getB() == null) {...}
>>>
>>> The problem is that even if there isn't a B associated with A, OJB
>>> returns
>>> false because there is always a proxy between A and B. The check is
>>> actually
>>> done using the proxy reference which is always present.
>>> How can we handle that?
>>>
>>
>> Which version of OJB do you use? I try to reproduce this with the
>> current source (OJB_1_0_RELEASE branch) without success. If class
>> Article has a 1:1 relation to ProductGroup and I search for an Article
>> without a ProductGroup I get:
>>
>> Criteria c = new Criteria().addEqualTo("articleName", name + "without
>> PG");
>> q = QueryFactory.newQuery(ArticleWithReferenceProxy.class, c);
>> Article br = (ArticleWithReferenceProxy) broker.getObjectByQuery(q);
>> assertNotNull(br);
>> assertNull(br.getProductGroup());
>>
>> Could it be that the association between A and B is a 1:n relation?
>>
>> regards,
>> Armin
>>
>>> Thank in advance!
>>
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>>
>
>
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