I agree and am not sure why you have doubts?

Sent from my iPhone

Michael McGrady
Principal investigator AF081_028 SBIR
Chief Architect
Topia Technology, Inc
Work 1.253.572.9712
Cel 1.253.720.3365

On Jan 30, 2011, at 9:59 PM, Patricia Shanahan <[email protected]> wrote:

> I wish it had been phrased in the same terms as the JLS. I know the write 
> call completion happens-before the call to the read method. I think that 
> means the same as "the write returns before the read commences" but I'm not 
> sure.
> 
> Patricia
> 
> 
> 
> 
> MICHAEL MCGRADY wrote:
>> There is this, which I assume you have already seen?
>> Operation Ordering
>> Operations on a space are unordered. The only view of operation order can be 
>> a thread's view of the order of the operations it performs. A view of 
>> inter-thread order can be imposed only by cooperating threads that use an 
>> application-specific protocol to prevent two or more operations being in 
>> progress at a single time on a single JavaSpaces service. Such means are 
>> outside the purview of this specification.
>> For example, given two threads T and U, if T performs a write operation and 
>> U performs a read with a template that would match the written entry, the 
>> read may not find the written entry even if the write returns before the 
>> read. Only if T and U cooperate to ensure that the write returns before the 
>> read commences would the read be ensured the opportunity to find the entry 
>> written by T (although it still might not do so because of an intervening 
>> take from a third entity).
>> On Jan 30, 2011, at 7:42 PM, Patricia Shanahan wrote:
>>> Suppose thread A writes an item to a JavaSpace, thread B attempts to read 
>>> it, and A's call to the space's proxy write method happens-before B's call 
>>> to the space's proxy read method. There are no transactions involved
>>> 
>>> Should the read always succeed?
>>> 
>>> In other words, should a happens-before relationship between two actions in 
>>> a client imply a corresponding happens-before relationship between the 
>>> corresponding actions in the actual space, without depending on transaction 
>>> semantics?
>>> 
>>> This question affects whether I'm working on a bug in outrigger or in one 
>>> of its tests.
>>> 
>>> Thanks for any information.
>>> 
>>> Patricia
>> Michael McGrady
>> Chief Architect
>> Topia Technology, Inc.
>> Cel 1.253.720.3365
>> Work 1.253.572.9712 extension 2037
>> [email protected]
> 

Reply via email to