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
mmcgr...@topiatechnology.com
