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Date: Mon, 17 Sep 2007 16:46:48 +0200
From: Marcel Reutegger <marcel.reutegger@gmx.net>
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To: dev@jackrabbit.apache.org
Subject: Re: Synchronized methods in ItemManager
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Julian Reschke wrote:
> Marcel Reutegger wrote:
>> Julian Reschke wrote:
>>> Marcel Reutegger wrote:
>>>> our official statement still is you may use multiple threads on a 
>>>> session that just read but a single thread on a session that writes. in 
>>>
>>> - Could you please provide a pointer to that statement?
>>
>> well, maybe 'official' is the wrong term. whenever these kind of 
>> questions arise on the mailing list, we tell people that reading from 
>> multiple thread is probably safe, while writing is not. searching the 
>> mail archive should give you some of those statements.
> 
> I see. Note that you now said "is probably safe" :-)

yeah, I looked up the relevant messages in the archive and found that we only 
say 'probably' ;)

>>> Finally, how does that translate to JCR2SPI and the SPI interfaces? 
>>> It seems we need to clarify the thread-safety of 
>>> spi.RepositoryService and spi.SessionInfo...
>>
>> I agree, we should definitively do that. Again, I think jcr2spi should 
>> be entirely thread safe for any kind of operation, while the SPI level 
>> is IMO debatable, because it is at a lower level.
> 
> FWIW, we should make up our minds what we want to agree, and clearly 
> document that. I don't care a lot about what we say, but I'm not 
> convinced that guaranteeing more than JSR-170 says would be good for 
> interoperability of clients.

well, the main reason behind my call for a thread-safe implementation is for 
clients that use a session from multiple sessions *by mistake* and not on 
purpose. the repository should not break in any case.

regards
  marcel