[foreign-memaccess] RFR 8234581: Cleanup use of exceptions in the memory access API

[sundararajan.athijegannathan at oracle.com]

Looks good.

Minor:

+

private static boolean skipZeroMemory;
+
+static {
+skipZeroMemory = 
GetBooleanAction.privilegedGetProperty(“jdk.internal.foreign.skipZeroMemory”);
+}


could be static final & inline initialization.

-Sundar

On 21/11/19 6:23 pm, Maurizio Cimadamore wrote:
> New day, new cleanup :-)
>
> This time, following some of the indications from Paul, the goal is to 
> cleanup usages of exceptions in the memory access API. I found 4 broad 
> categories of issues:
>
> - We sometimes throw IAE where an IOOB would be preferred (namely, 
> MemorySegment::slice and MemoryAddress::copy)
>
> - We sometimes use RuntimeException to document unforeseen failures of 
> Unsafe::allocateMemory (ByteBuffer::allocateDirect does not do so)
>
> - The handling of exceptions when forming layout paths is plain 
> inconsistent - and IAE should be used throughout
>
> - MemorySegment::close should always throw ISE if the state is not valid
>
>
> The changes in LayoutPath handling required some deeper changes in the 
> implementation - which now triggers an uniform IAE with a message of 
> the kind: Bad layout path: <cause>.
>
>
> Since I was there, I also added the logic to zero the native memory 
> allocated with MemorySegment::allocateNative. This behavior can be 
> disabled with a runtime flag: -Djdk.internal.foreign.skipZeroMemory.
>
>
> I also made extra sure that the exceptions thrown in the code are 
> reflected in the throws clause of the API methods, and that there are 
> the right @throw taglets for them.
>
> Webrev:
>
> http://cr.openjdk.java.net/~mcimadamore/panama/8234581/
>
> javadoc:
>
> cr.openjdk.java.net/~mcimadamore/panama/8234581_javadoc
>
>
> Cheers
> Maurizio
>