Hi,
Consider the following class libraries:
[A] Suns rt.jar and derivatives (such as IBMs) class libraries
[B] GNU Classpaths class libraries
[A] has a proprietary VM interface that is not publicly documented and
some people fear looking at the implementation because of possible "taint"
(IMHO with the new license this is less of an issue).
[B] has an interface that is relatively well documented but incomplete.
AFAIK no one has done any investigation to see if [A] could be retrofitted
to use [B]'s VM interface with minimal changes.
Both [A] and [B]
* can arbitrarily change between versions.
* have been integrated into multiple JVMs
In an ideal world Harmony VM would be able to use either [A] or [B]
with a small adapter layer. Much like MMTk can be used in multiple VMs
with a small adapter layer.
It seems unlikely that either [A] or [B] is going to invest the time in
trying to
develop a common VM interface because they are not interested in
facilitating
reuse of the alternative. So it is probably going to be up to a third
party like
Harmony to investigate a common VM layer.
Personally I suspect that it is going to be a LOT of work and even then
I am not
sure it is going to be possible either technically or politically but it
is an interesting
idea and worth trying.
--
Cheers,
Peter Donald
"Nothing changes your opinion of a friend so surely
as success - yours or his." - Franklin P. Jones