Hi,
I answered on the PR on github. The documentation is misleading:
The copypasted snippet above is misleading, you need to read the
whole statement, so an IllegalStateException can only happen for
unaligned access on access modes other than get/set (so volatile or
opaque reads): "If access is misaligned then access for
anything*other than the get and set access modes*will result in an
IllegalStateException.", the sentence you posted is about if it is
atomic or not. It just says that on 32 bits, long/double are not
atomic for normal set/get.
P.S.: We definitely know that it works on 32 bit, the whole code of
Lucene is full of those VarHandles :-)
And no, it doe snot mean "get-and-set". Read the whole text, it is
definitely correct, but if you don't read everything it may mislead you.
So it can be improved.
Uwe
Am 05.01.2023 um 13:31 schrieb Michael Kuhlmann:
The more I think about it, the clearer is that the first line of the
Javadoc is contrary to the other lines:
On 1/5/23 12:59, Michael Kuhlmann wrote:
* read write access modes for all T, with the exception of access
modes get and set for long and double on 32-bit platforms.
So all read write modes will work, just if it's long or double then it
won't work for get and for set access mode. (Or is getAndSet meant?
But it's not called so, it's "get and set", so two access modes, or
what?)
Then the following lines state that even harder access modes will work
also for long and double.
So I think this should be labeled as "getAndSet" or at least
"get-and-set" access mode. Currently it's very confusing.
--
Uwe Schindler
uschind...@apache.org
ASF Member, Member of PMC and Committer of Apache Lucene and Apache Solr
Bremen, Germany
https://lucene.apache.org/
https://solr.apache.org/
