Implement no copy memory

[Maurizio Cimadamore]

On 21/05/2019 05:26, Ardika Rommy Sanjaya wrote:
> If using panama should I cast the Pointer<Byte> before get the content 
> data?

In Panama you would do this:

Pointer<Byte> buf = ...

Pointer<Short> ps = buf.cast(NativeTypes.VOID).cast(NativeTypes.UINT16);
short s = ps.get();

or...

Pointer<Integer> pi = buf.cast(NativeTypes.VOID).cast(NativeTypes.UINT32);
int i = pi.get();

Note that you have to cast through VOID first, otherwise the Panama 
runtime will complain about incompatible cast.

I believe we can relax these rules for cast compatibility a bit - we 
have some ideas in mind there [1].

[1] - 
https://mail.openjdk.java.net/pipermail/panama-dev/2019-February/004665.html

>
> For example if I want to get 2 byte and then 4 byte with Unsafe I can 
> do like below:
>
> Unsafe UNSAFE = ...
>
> UNSAFE.getShort(..)
> UNSAFE.getInt(...)
>