Hi, Developers,

I am reading Hibernate in Action book. page 300-304.
in this part, the book is about thread local seesion pattern.
From HibernateUtil code:

private static final ThreadLocal threadSession = new ThreadLocal();
private static final ThreadLocal threadTransaction = new ThreadLocal();

looks like all request will share the same seesion.
This is what I am confuesed, if 2 different users place bid at the same time, they will use the same threadSession, right?

So if my thought is right, The problem will be here.

From void dofilter() { // (page 304)
.......
......
finally {
HibernateUtil.closeSession();
}


}
After the first user rendered the view, the session will be closed. then the second user has not rendered the view, the newbid.getBidder().getItems().iterator() is unfetched at this point because of items association is lazy.


How to fix this issue?

if ThreadLocal threadSession is not static, so the different will have different session? right.

Thank you much for your help!

Edgy

ThreadLocals explained:
http://www-128.ibm.com/developerworks/j ... eads3.html

Thanks, Frankgrimes,

Sorry I am not sure your name.
I am still confused.
From this code, because threadSession is static, so all threads will share the same session. I don't know where I am worng. Please help me, Thank you.

Edgy

public class HibernateUtil {
...
private static final ThreadLocal threadSession = new ThreadLocal();
..

public static Session getSession()
throws InfrastructureException {
Session s = (Session) threadSession.get();
try { if (s == null) {
s = getSessionFactory().openSession();
}
threadSession.set(s);
}
}
return s;
}

No they won't. You obviously haven't read the link Frank provided.

private static final ThreadLocal threadSession = new ThreadLocal();
..

public static Session getSession()
throws InfrastructureException {
Session s = (Session) threadSession.get();
try { if (s == null) {
s = getSessionFactory().openSession();
}
threadSession.set(s);
}
}
return s;
}

threadSession is a ThreadLocal, ThreadLocal has a feature of store value in the thread which r u accessing means

From Thread1 I am calling like this

run(){
Util.getSession();
}

Here Thread1 is calling the getSession(), First it will call the threadSession.get() means nothing but in the Thread1's threadlocalmap is containing session or not, if it is not contain session it will give null, then we are creating the new session, the created session we are storing Thread1's threadlocalmap.

In your case Thread1 and Thread2 are calling getsession means each Thread1 and Thread2 have their session only when their calling the getsession().

Alternatively, the two users hit the server starting two separate threads of execution.