I need some advice on how to keep objects in the session when working with long sessions (as described in Hibernate in Action p. 325 8.2)

I would like to keep some object always bound to the current session, like for example, the user context object, after logging in to the system. This is very convenient, as the user object is always used somehow in the views.

So I always want to keep the user object around. This works smoothly until I want to start a application transaction, for example when I want to create a new user.

When I need to update an object or create new objects, I start a new application transaction, as shown in the book, and the session is cleared.

request 1: HibernateUtil.newApplicationTx();
..
request n: HibernateUtil.commitApplicationTx();

After that requests, accessing the user object sometimes works, sometimes not. Currently, the only safe way I found is to reload the object in each request, like this:


I also tried this:



This seems to work, but sometimes I get a lazy-Exception.
So my question: What is the correct way? Always reload the objects in every request?

Thanks in advance,

Axel

Correct way is to store "userid" in httpsession and It makes sence to use "global" cache if objects is used by all requests (reload it from database or cache once per transaction/request ).

Hi,

so if I understand correctly, I really should reload the object with:



in every request? That was the only way that always worked. In fact, I put the corresponding object in the second level cache, is that what you are suggesting?


Thanks,

Hi Axel,

As suggested previously, You may consider the usage of secondar level cache. Hibernate is bundled with ecache.

You may enable this cache by setting up the Hibernate.cfg.xml.

<property name="hibernate.cache.use_second_level_cache">true</property>

You may also need the ecachexxx.config.xml file.

Hope it helps.

Yes, this is simple and "safe" way.