On 05 Dec 2003 16:21, yvanhess wrote:

>We also use the Oracle CLOB custom type solution in our application.
>Can you explain more in detail the solution/the pattern to solve the
>resource leak problem.

It's simple, but making it work in your environment might not be. You
need to execute this statement after you're done with the CLOB: 
---
oracle.sql.CLOB.freeTemporary(temporaryClob);
---

I wanted to make this non-intrusive, so that user of the CLOB mapper
would not need to manually code the release (which would render mapper
useless). So I hooked cleanup code to a transaction listener and hooked
the listener to the UserTransaction. If you're not using JTA, you will
have to find some other hook. It will be all much easier when Hibernate
gets proper event handling.

Code illustration:
---
Context ctx = new InitialContext();
Transaction t =
((TransactionManager)ctx.lookup("java:comp/UserTransaction")).getTransaction()
t.registerSynchronization(new Synchronization()
{
  public void beforeCompletion()
  {
// temporaryClob is the temp. CLOB created by the mapper. Variable must 
// of course be final for this to work and in scope.
    oracle.sql.CLOB.freeTemporary(temporaryClob);
  }
  public void afterCompletion(int i)
  {
    // nothing to do here
  }
});
---