How to clear Session.Transaction property

zetta · **Joined:** Tue Oct 11, 2005 2:29 am **Posts:** 2

I use following pattern with Nhibenate transaction:

using (ITransaction tr = session.BeginTransaction())
{
// data update
tr.Commit();
}

But commiting/rolling back (disposing) transaction doesn't clear Session.Transaction property. So following out-of-transaction operation are failed because of disposed transaction.

I have considered three workaround:
1) Begin new transaction after this one. (bad solution - i don't need transaction in followed operations)
2) Implement own dummy ITransaction and use it for nontransactional stub.
3) Dispose session and use another one.

I have looked through the sources and didn't found any way to clear SessionImpl.transaction after it was disposed.
I wonder if such behaviour is feature or bad design.

Grace · **Posted:** Tue Oct 11, 2005 3:28 am

A good practice is to keep the session as short as possible. So, open a new session, do job and close the session.
Personnaly, I create a DAL (Data Access Layer) class (called DatabaseManager) which contains all the functions I need to access datas.
So, I call the functions of this class in all my BLL (Business Logic Layer) classes.

[code]
using System;
using System.Collections;

using NHibernate;
using NHibernate.Cfg;

namespace GestionnaireDeCandidatures.DAL
{
/// <summary>
/// Couche d'acc

KPixel · **Posted:** Tue Oct 11, 2005 9:42 am

Zetta, your 3) is the way to go.

Grace, I think that your session instance should be a local instance like transaction.

On side note, did you test prepareToGC() to see if it really has any effect? Anyway, I don't think it is really useful.
And you should replace "throw e;" by "throw;"...

zetta · **Joined:** Tue Oct 11, 2005 2:29 am **Posts:** 2

I don't like disposing session because it breaks session-per-request strategy in my app.
So i have created dirty hack to solve my need:

Code:

private static FieldInfo transaction = null;
public static void ClearSessionTransaction()
{
   if (transaction == null)
   {
      Assembly nhib = Assembly.Load("NHibernate");
      foreach (Type type in nhib.GetTypes())
         if (type.FullName == "NHibernate.Impl.SessionImpl")
         {
            transaction = type.GetField("transaction", BindingFlags.NonPublic | BindingFlags.Instance);
            break;
         }
   }
   transaction.SetValue(DefaultSession, null);
}

PS I don't recomend this way, but it best for me.