[foreign-memaccess] RFR: 8248487: Add static helpers to access segments [v3]

[Jorn Vernee]

On Tue, 30 Jun 2020 21:55:58 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

>> This patch addresses some usability issues in the foreign memory API. First, it adds several static accessors for all
>> carrier types in MemoryLayouts (I'm thorn whether to add this in MemoryLayouts or MemoryHandles, suggestions welcome).
>> These accessors provide an access API that is similar to unsafe - all accessors expect a base address plus a byte
>> offset. In most cases the accessors can be used and direct VH usage can be dropped, which might make approaching this
>> API a bit easier.  Secondly, I've added a bunch of helpers to map a segment into _any_ array (as opposed to just
>> `byte[]`). This makes the API more symmetric, given that, after all we _were_ able to create a segment from _any_ array
>> (not just `byte[]`).
>
> Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update src/jdk.incubator.foreign/share/classes/jdk/incubator/foreign/MemoryLayouts.java
>   
>   Co-authored-by: Henry Jen <henryjen at ztune.net>

Marked as reviewed by jvernee (Committer).

src/jdk.incubator.foreign/share/classes/jdk/incubator/foreign/MemoryAccess.java line 16:

> 15:         // just the one
> 16:     }
> 17:

Should be private I guess:
Suggestion:

    private MemoryAccess() {
        // just the one
    }

-------------

PR: https://git.openjdk.java.net/panama-foreign/pull/221