Good morning guys,

I'm working in a system that mostly uses JPA2 to work with persistence. but in some cases, we need to execute some gigantic select queries and map them to a DTO (not using any entity).

the JPA way of doing it is to execute a nativeQuery and map the resultSet using @SqlResultSetMapping but this annotation is incredibly cumbersome.

So I'm trying to implement a way to get a connection and execute it through the JDBC way, and then I'll be using apache dbutils to map the resultSet.

The problem: I'd like to obtain this connection from the entityManager, or at least get the datasource configuration from persistence.xml.
So I was thinking in 3 possible solutions with the following questions:

1) unwrap the connection (probably I'd have to be inside a transctional context, but anyway, how can I do that with hibernate?)
2) get the datasource name from jpa api, something like: entityManagerFactory.getProperties().get("datasource.name") (this don't work though, so is there another way to get it?)
3) in case hibernate provides a different way to map the resultset, forget this approach and use this feature. (does hibernate provides something like this?)

how can I access the PersistenceUnitInfo ?
http://docs.oracle.com/javaee/6/api/jav ... tInfo.html

Good morning,

Maybe I could use the nativeQuery with another tool to use the resultSetMapping, something similar to what apache dbutils provides.
Do you guys know anything like that?

if you're using hibernate, then try unwarp a session, and do session.doWork(), this method requires a Work intance, which will give you a connection

Hi Stliu,

What is a "Work" exactly in hibernate context?

I was trying to create a CDI producer to provide a datasource OR a connection to someone using like:


that datasource/connection would have to come from the same context as an entityManager
so, using work, could I try something like this to obtain the connection?



I feel that something is not in place. Besides that with I'm getting a weird exception when using this producer

http://pastie.org/2970661

I understood that is for the best to not obtain the connection but to run a work inside the doWork method.
I won't provide the connection to an unbound operation. instead I'll use it as the api suggests.

thank you Stliu.