ThreadLocal bug

[Marco Mistroni <mm...@waersystems.com>]

Hello,
	I have seen in apache  buglist a bug regarding ThreadLocal

I am using threadLocal in one of the classes used by my webservice...(I
am
Using Hibernate in my webservice)

Can anyone tell me what that bug was about?
As a matter of fact my code that uses ThreadLocal does not work.....

Thanx in advance and regards
	Marco

Re: ThreadLocal bug

["matthew.hawthorne" <ma...@apache.org>]

Joseph Dane wrote:
> "matthew.hawthorne" <ma...@apache.org> writes:
> 
>>I'm not sure if this is it -- but ThreadLocals don't work inside of
>>app servers that use thread pooling.
> 
> 
> that's news to me.  care to clarify this?
> 
> perhaps you mean that for a series of requests coming as part of a
> single session, the several requests aren't guaranteed to be serviced
> by the same thread.  which is true, but a far cry from "ThreadLocals
> don't work inside app servers using thread pools". 


Here's what I meant:

In servers that use thread pooling, ThreadLocal variables may not be 
unique for each request.

I was using ThreadLocals to store invocation information, specific to 
each request.  But I noticed that, in some requests, instead of the 
intialValue() method being called to initialize the ThreadLocal, it was 
simply getting the already-initialized value.  After doing some further 
investigation and checking Thread.currentThread() and such, I realized 
that the same Thread was being used for multiple requests, which 
eliminated the uniqueness for each request that I needed to maintain.

Like I said in my earlier email, my technique was overly complicated.  I 
was able to solve the problem by using Axis' 
MessageContext.getCurrentContext().

But you're right -- after re-reading what I wrote, I realized that I had 
phrased it terribly.  ThreadLocals were working exactly the way that 
they're supposed to, I just didn't understand the way that the server 
managed its threads.

Re: ThreadLocal bug

[Joseph Dane <jd...@hawaii.edu>]

"matthew.hawthorne" <ma...@apache.org> writes:

> I'm not sure if this is it -- but ThreadLocals don't work inside of
> app servers that use thread pooling.

that's news to me.  care to clarify this?

perhaps you mean that for a series of requests coming as part of a
single session, the several requests aren't guaranteed to be serviced
by the same thread.  which is true, but a far cry from "ThreadLocals
don't work inside app servers using thread pools".

-- 

joe

Re: ThreadLocal bug

["matthew.hawthorne" <ma...@apache.org>]

Marco Mistroni wrote:
> Hello, I have seen in apache  buglist a bug regarding ThreadLocal
> I am using threadLocal in one of the classes used by my webservice...(I
> am Using Hibernate in my webservice)
> 
> Can anyone tell me what that bug was about?
> As a matter of fact my code that uses ThreadLocal does not work.....

I'm not sure if this is it -- but ThreadLocals don't work inside of
app servers that use thread pooling.

I ran into this problem with JBoss a while back, and had to use a 
different technique to do what I wanted.

I was able to just use a basic HTTP session instead, which is probably
simpler anyway.