Another revision which addresses some additional CSR feedback:
* SequenceLayout::withElementCount should throw if new element count < 0
* MemoryLayout::hasSize should clarify that certain layout (e.g.
ValueLayout) always have a size
Webrev:
http://cr.openjdk.java.net/~mcimadamore/8235837_v3
delta from previous iteration:
http://cr.openjdk.java.net/~mcimadamore/8235837_v3_delta
javadoc
http://cr.openjdk.java.net/~mcimadamore/8235837_v3_javadoc
specdiff
http://cr.openjdk.java.net/~mcimadamore/8235837_v3_specdiff/overview-summary.html
Cheers
Maurizio
On 09/01/2020 18:36, Maurizio Cimadamore wrote:
New revision:
http://cr.openjdk.java.net/~mcimadamore/8235837_v2
delta from previous iteration:
http://cr.openjdk.java.net/~mcimadamore/8235837_v2_delta
javadoc
http://cr.openjdk.java.net/~mcimadamore/8235837_v2_javadoc
specdiff
http://cr.openjdk.java.net/~mcimadamore/8235837_v2_specdiff/overview-summary.html
Cheers
Maurizio
On 09/01/2020 14:36, Maurizio Cimadamore wrote:
Hi,
following the JEP 370 code review and CSR, certain comments that have
not been addressed have been added to the tracker issue:
https://bugs.openjdk.java.net/browse/JDK-8235837
For further evaluation. After some discussion in the Panama channel
(see [1] and [2]), the Panama team has come to the following
conclusions:
* the MemoryAddress::offset(long) method should be renamed to
MemoryAddress::addOffset(long)
* the MemorySegment::isAccessible() predicate should be dropped and
replaced with the MemorySegment::ownerThread() accessor
* a new predicate should be added to MemoryLayout, namely
MemoryLayout::hasSize() to allow clients to establish as to whether a
layout contains some unsized parts
* a new method should be added to SequenceLayout, namely
SequenceLayout::withElementCount, to create a new sequence layout
with new element count
* 2 new helper methods should be added to MemoryLayout, namely:
- MemoryLayout::map - to allow transformation of a layout into a
new layout (by replacing the sub-layout at given path with a new layout)
- MemoryLayout::select - to allow selection of a sub-layout given
a layout path
Overall, we think this set of change strikes a good compromise
between usability, readability and minimality.
The javadoc for the layout path-accepting methods (both old and new
ones) has been significantly refactored and improved - and the
toplevel javadoc section on layout paths has been enhanced to cover
all the concepts. The implementation for these methods has also been
consolidated greatly, which revealed subtle bugs in the old
implementation which have now been rectified (new tests have been
added).
Webrev is available here:
http://cr.openjdk.java.net/~mcimadamore/8235837/
Specdiff for changes here:
http://cr.openjdk.java.net/~mcimadamore/8235837_specdiff/overview-summary.html
A draft CSR for this issue is available here (I will finalize once
the review converges on the API changes):
https://bugs.openjdk.java.net/browse/JDK-8236853
I plan to push this to JDK 14 under the late enhancement process [3].
Cheers
Maurizio
[1] -
https://mail.openjdk.java.net/pipermail/panama-dev/2019-December/006873.html
[2] -
https://mail.openjdk.java.net/pipermail/panama-dev/2019-December/006885.html
[3] - https://openjdk.java.net/jeps/3#Late-Enhancement-Request-Process
