indy and tailc

[John Rose]

On Jan 27, 2010, at 1:03 AM, Patrick Wright wrote:

> On Wed, Jan 27, 2010 at 9:45 AM, John Rose <John.Rose at sun.com> wrote:
>> On Jan 27, 2010, at 12:30 AM, Patrick Wright wrote:
>> 
>>> Is the EG considering Anonymous classes for JSR 292?
>> 
>> No, sorry.  Should we be... what's the use case?  -- John
> 
> From
> what I read on this mailing list, Charles Nutter for example was quite
> excited to have them.
> 
> I may have misunderstood the point of ACs, however.

They also provide a way to do something like bytecode-level templating, since CP elements can be varied while the rest of the code is held fixed.  I hope somebody experiments with loop customization at some point, using anonymous classes or a higher-level bytecode weaver.  But that's in the future.

The uses you and Charlie point out are less important that they seemed at first for two reasons:

1. Method handles provide a better replacement for the swarm of tiny classes.

2. Hotspot is in the process of weaning itself off of perm gen.  One of the main features of perm-gen is that its objects never move except during full GC, and the code cache relied on this invariant until just last year, with the 'ScavengeRootsInCode' changes.

-- John