Re: Classpath build process and VM-specific issues

[Per Bothner]

Jeroen Frijters wrote:

> That's why I'm very much in favor of using RawData.  ...
>
> public abstract class RawData {}
>
> public final class RawData32 extends RawData
> {
>   private int pointer;
> }
>
> public final class RawData64 extends RawData
> {
>   private long pointer;
> }
>
> All the Java code would ever see are RawData references, but the JNI
> layer knows that all RawData references are actually 32 or 64 bit (or
> whatever that platform requires).

But this is a completely different model than the CNI RawData,
since you're adding an extra layer of indirection.

In CNI, a RawData is not an object that *contains* a pointer;
the pointer is the RawData reference itself.

I.e.
inline void* RawData_to_pointer (RawData *rd)
{
  return (void*) (rd);
}

*not*

inline void* RawData_to_pointer (RawData *rd)
{
  return (void*) (rd->pointer);
}

Adding the extra indirection seems like a bad idea to me.
I'd rather use jlong.  But I don't see any real reason not to
use RawData.  I can see on a few JVMs it may cause problems,
but they can easily sed the source to convert RawData to long.
Just think of RawData has a macro.
--
        --Per Bothner
address@hidden   http://per.bothner.com/